Ham Radio in Plain English

HA M RA DI O IN P L AIN ENG LI SH A Step-By-Step Guide For Regular Peopl"

by Randy Pryor

Ham Radio In Plain English

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Copyright Notice Copyright © 2005 Randy Pryor All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, mechanical or electronic, including photocopying and recording, or by information storage and retrieval system, without permission in writing from the publisher. Requests for permission or further information should be emailed to: [email protected]

Legal Notices While all attempts have been made to verify information provided in this publication, neither the author nor the publisher assumes any responsibility for errors, omissions or contrary interpretation of the subject matter herein. The Publisher wants to stress that the information contained herein may be subject to varying state and/or local laws or regulations. All users are advised to retain competent counsel to determine what state and/or local laws or regulations may apply to the user’s particular operation. The purchaser or reader of this publication assumes responsibility for the use of these materials and information. Adherence to all applicable laws and regulations, both federal and state and local, governing professional licensing, operation practices, and all other aspects of operation in the United States or any other jurisdiction is the sole responsibility of the purchaser or reader. The publisher and author assume no responsibility or liability whatsoever on the behalf of any purchaser or reader of these materials. Any perceived slights of specific people or organizations is unintentional.


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TABLE OF CONTENTS Introduction

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Meet the Gang

CHAPTER 1 - THE WORLD OF AMATEUR RADIO! ! !

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Purpose of Amateur Radio ! ! ! ! Operating a Ham Radio: Making Contacts! Ragchews! ! ! ! ! ! ! Nets! ! ! ! ! ! ! ! Traffic Nets ! ! ! ! ! ! Emergency Service Nets! ! ! ! ALE Mailboxes and Bulletin Boards ! ! Full Duplex Operation! ! ! ! ! Swap Nets! ! ! ! ! ! ! DX-ing, Contests, and Awards! ! ! Ham Radio and Ordinary Radio! ! ! Transceiver! ! ! ! ! ! Cost of Equipment! ! ! ! ! Setting Up Ham Radio Equipment! ! ! Bandwidth Selection! ! ! ! ! Some Points for Beginners! ! ! ! ‘To Listen’ is the Phrase! ! ! ! Contacting Your Nearest Club! ! ! Finding One in the Same Boat ! ! ! Know Your Equipment! ! ! ! ! Use All Resources ! ! ! ! ! Practice Courtesy! ! ! ! ! Be Cool ! ! ! ! ! ! ! Ham and Phonetics! ! ! ! ! Operation Using Computers ! ! ! ! Satellites! ! ! ! ! ! ! Amateur Radio on Boats! ! ! !


15! 15! 16! 16! 17! 17! 17! 17! 17! 17! 18! 18! 18! 19! 20! 21! 21! 21! 21! 22! 22! 22! 22! 23! 23! 23 24! 24!

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Signal Reports (the RST code)! ! ! ! ! International Q-Code (Extract)! ! ! ! ! Continuous Wave Transmitter Web Sites for Buying Equipment and Electronic Circuits Buying Old Equipment The Statistics of Ham Radio Users Making of a Simple QRP Rig !

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CHAPTER 2 - BASICS OF RADIO WAVE TRANSMISSION Mode of Radio Wave Transmission Propagation of VHF Signal Reflection of VHF/UHF Signals The Process of Ionization in the Ionosphere The Ionosphere Layers The F Layer The E Layer The D Layer Critical Frequency

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CHAPTER 3 - FACTORS AFFECTING RADIO WAVE TRANSMISSION 37 Factors Affecting Radio Waves Absorption Fading Losses Due to Ground Reflection Free Space Loss Electromagnetic Interference Radio Waves and Weather Ducting Earth Moon Earth Satellite Sunspots

CHAPTER 4 - TRANSMISSION THEORY Transfer of Radio Waves from the Transmitter to the Antenna Transmission Line Theory


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Lumped Constants Distributed Constants Inductance of a Transmission Line Capacitance of a Transmission Line Resistance of a Transmission Line DC Applied to a Transmission Line AC Applied to a Transmission Line

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CHAPTER 5 - ANTENNA

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Antennas The Basic Antenna Energy Distribution on an Antenna Radio Wave Modulation Morse Code Modulation Radiation of Electromagnetic Energy Antenna Gain Antenna Reciprocity Radiation Resistance Isotropic Radiation Anisotropic Radiation Antenna Loading Antenna Positioning Types of Different Antennas Half –wave Antennas! ! ! ! Quarter –wave Antennas! ! ! Horizontal Dipole Inverted V Folded Dipole Directional Antennas Parasitic Antenna Yagi Antenna One Antenna for Different Bands Terminology Used in Array Antennas Driven Element Parasitic Element Driven Array Ham Radio In Plain English

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Bi-directional Array Unidirectional Array

CHAPTER 6 - HAM RADIO LICENSE FCC Control Operator Amateur Radio License License Classes Renewal of the License Changes Made by the FCC in 2000 Expired License VHF/UHF Bands VHF Bands Image Transmissions Station Licensee Identification Third Party Communications Frequency Sharing Power Limits Language Beacons Distress Transmission and Dummy Load Repeaters Station License Required Control Operator Required Operator License Stations aboard Ships or Aircraft Restrictions on Station Locations Station Antenna Structures Application for New License or Reciprocal Permit for Alien Amateur Licensee Application for a Modified or Renewed License Mailing Address License Term FCC Modification of Station License Ham Radio In Plain English

59 59 60 60 60 60 60 61 61 62 63 64 64 64 65 65 65 65 66 66 66 66 66 67 69 69 70 70 70 72 73 74 75 75 6

Replacement License Document 76 Subpart B--Station Operation Standards 76 General Standards 76 Station Licensee Responsibilities 76 Control Operator Duties 77 Alien Control Operator Privileges 77 Station Control 78 Authorized Transmissions 79 Prohibited Transmissions 80 Third Party Communications 81 International Communications 82 Station Identification 83 Restricted Operation 84 Subpart C--Special Operations 85 Auxiliary Station 85 Beacon Station 86 Repeater Station 87 Space Station 88 Earth Station 89 Space Telecommand Station 90 Telecommand of an Amateur Station 90 Telecommand of Model Craft 91 Telemetry 91 Message Forwarding System 91 Subpart D--Technical Standards 92 Frequency Sharing Requirements 92 Emission Standards 97 RTTY and Data Emission Codes 100 SS Emission Types 101 Transmitter Power Standards 103 Type Acceptance of External RF Power Amplifiers 104 Standards for Type Acceptance of External RF Power Amplifiers 105

CHAPTER 7 - AMATEUR RADIO PRACTICE Safety Lightning Damage Ham Radio In Plain English

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Safety of the Station Grounding What is a Ground? ! ! ! ! Power Line Ground DC Ground (Safety Ground) RF Ground High Voltage Power Supplies Antenna Safety Safety of the Equipment Hazardous Voltages Standing Wave Ratio (SWR) SWR Readings - How Are They Rated? Fixing a Bad SWR Reading Lengthening Shortening Meters and Measurements Voltmeter Ammeter Multimeter RF Wattmeter Directional Wattmeter Peak Reading Wattmeter Oscilloscope Audio Wave Modulation Morse Code Modulation !

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Chapter 8 - ELEMENTARY ELECTRICITY ‘God of Small Things’! ! ! Points to Remember Cells Connected in Series Cells Connected in Parallel The Direction of Current Flow What is Electric Current? Properties of Electric Current Conductors Ham Radio In Plain English

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Extrinsic Semiconductors – P and N Type! Pn Junction Diodes Pn Junctions Formation of Pn Junction Properties of Pn Junction Transistors Base Emitter and Collector Layers Vacuum Tubes

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Chapter 9 - MAGNETISM AND BASIC ELECTRIC DEVICES

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Electric Potential Potential Difference Resistance Capacitors Schematic Symbol for a Capacitor Equivalent Series Resistance of a Capacitor (ESR) Film Capacitors Electrolytic Capacitors Capacitor and Voltage Electric Field Alternating Current Magnetism Types of Magnets Magnetic Poles and Forces Magnetic Fields Circuit Theory Types of Circuits Circuit Components The Objective of a Resistor Light Dependent Resistor Capacitor Temperature Sensors Microphone Switch

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Fuse Voltmeter Ammeter Multimeter Circuit Equations

Chapter 10 - TRANSMISSION OF ELECTRICITY Structure of Electric Power Systems Distribution Transmission and Distribution

Chapter 11 - ELECTROMAGNETIC WAVES AND RADIO WAVES Electromagnetic Waves Basics of Wave Motion Wavelength Amplitude Frequency Radio Waves Units of Frequency Bandwidth The Factors Affecting Radio Waves

Chapter 12 - A PEEP INTO THE ATMOSPHERE What Is Atmosphere? Troposphere Stratosphere Ionosphere Conclusion


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HA M RA DI O IN P L AIN ENG LI SH A Step-By-Step Guide For Regular Peopl"

Introduction “The radio has no future.” ~ Lord Kelvin, British mathematician 1897 People’s interests range from the fun to the weird to the downright bizarre. Some jog, others collect porcelain knickknacks, while still others investigate the paranormal. A hobby is a reflection of a person’s character. Since humans are the most social of all animals, there is an inherent desire to establish contact and maintain relationships with others. When these two elements are joined together, they create the perfect hobby amateur radio.

What exactly explains the popular, cult-like following to ham radio? Perhaps it’s the unique mix of fun entertainment, public service, and convenience. It could be the satisfaction and accomplishment that arises when a person establishes contact with a fellow human being on the other side of the world with a gadget that seems much less Ham Radio In Plain English

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sophisticated than the Internet. There are various reasons why hams get involved in amateur radio, but they all have a basic knowledge of the technology, regulations, and operating principles that apply to radio in the first place. The Internet has greatly impacted the world with a new level of technology, but that does not take away the irresistible and timeless appeal of amateur radio. Perhaps it’s the idea of something old-fashioned in a modern world of high tech or maybe it’s the efficiency and simplicity that go hand in hand with the operation of amateur radio, but the appeal certainly has stood the test of time and space. Amateur radio is as old as the history of radio itself but the reason why amateur radio operators are called “hams” is rather obscure. Hams are a very mixed bunch. The two common things that hams share is the interest of what is happening in the world around them and using a radio to reach out. Some people prefer Morse code on an old brass telegraph via a low power transmitter, others opt for voice communication on a hand-held radio, and still others get their kicks from computer messages transmitted through satellites. These individuals come from all walks of life. They’re students, movie stars, truck drivers, sailors, and every profession imaginable. Their ages and interests are as varied as their careers.

A set of Antennas - The whole world within your reach


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It may sound like all fun and games, but the amateur radio set up is a very serious business. The radio has the ability to transmit life saving messages globally. In 1912, Congress passed the first laws regulating radio transmissions in the U.S. By 1914, amateur experimenters were up to their ears in this hobby and were communicating nationwide, so setting up a system to relay messages from coast to coast had become a necessity. The Federal Communications Commission (FCC) was created by Congress in 1927, and consequently, specific frequencies were assigned for various uses, including ham bands. The FCC created the Amateur Radio Service to lend a serious side to the hobby. Amateur radio could offer a pool of experts providing backup emergency communications in the face of critical times. In addition, the FCC acknowledged that amateur radio had the ability to enhance communication, improve the technical skills of radio, and boost international goodwill. This philosophy has definitely paid off. Countless lives have been saved because skilled hobbyists have acted as emergency communicators to render aid during earthquakes in Japan, floods in Indonesia, and epidemics in Africa. Most recently, Ham radio operators all over India became a lifeline as they helped locate and reunite countless families and assist in relief operations in the wake of the tsunami disaster.

Imagine yourself by the side of one of these.

If you’re wondering how hard is it to learn amateur radio, you may be relieved to know that just about anyone can learn enough to acquire a license easily. Only basic electronics and basic knowledge of radio operations are required.


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Over the years, three basic license classes have evolved. The higher the class license you have, the more privileges and modes of operation you receive. But each higher-class license requires extensive knowledge of technology, rules and regulations, as well as higher Morse code proficiency. So, you can learn the basics or you can become an expert and still enjoy the hobby.

Meet the Gang Here is a sampling of the individuals involved with amateur radio. Although hams usually consider it to be a hobby, amateur radio can be more than that – it can prove to be a life altering experience. This is Rose Robin; she was a witness to a motor accident along one of the national highways of our country. While driving to her parents’ home, she witnessed a horrific scene. She watched another car lose control, break the barricade, and speed off a cliff. Rose stopped her car and dashed to the scene of the accident. The car was overturned, its wheels spinning wildly. She raced to the car but found it impossible to yank the doors open to rescue the hapless mother and child trapped inside. Both were bleeding and unconscious. Rose’s quick thinking and critical desire to save a human life sent her dashing back to her car where she picked up her pocket-sized hand-held radio and radioed for help. Within minutes, police and an ambulance had arrived at the spot and could rescue the victims. Meet Josephine Williams, a lonely widow of 46. She lost her husband to cancer a year ago, and since then she has been living a rather cloistered life. No friends, no visitors, nothing. Mrs. Williams had not been very social when her husband was alive, but lately her loneliness had been eating into the very vitals of her existence. Being lonely is a thing of the past now, thanks to her radio. She has found two new friends who are fellow hams. One is a 23 year old martial arts student in Japan, and the other is an Indian male nurse working in Canada.


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Chapter 1 The World of Amateur Radio “Radio is just a fashion contrivance that will soon die out. It is obvious that there never will be invented a proper receiver!” ~ Thomas Edison Amateur radio has overcome many obstacles since its invention. Advances in technology have never hindered its path. In fact, the system has learned to cope with the technologies. A fine example is the contact made by two stations assisted by computers. The commercialization that has overtaken many other fields has not affected the hams. This is the sole reason why it is free for two hams to talk to each other, even across the globe. Also, if a disaster like an earthquake occurs, hams can provide critical help when most communication facilities are destroyed. Purpose of Amateur Radio Amateur radio stations’ key functions include self-training in radio communications, intercommunication, and investigations in radio communications. The individuals taking part in these activities should only get involved for personal reasons and not do it with any monetary interests in mind. The attitude or the essence of the amateur radio is the grouping together of people from different walks of life towards a common goal without any financial aims. This is a very important aspect since most people will do just about anything for money. We can state the purpose of ham radio in simple terms as to increase the number of trained radio operators and electronic experts by encouraging experimentation and enhance international goodwill. One with an interest in electronics and technology can really indulge in the realms of technical wizardry. When opening the hood of a ham radio, there is basic and there is innovative. The basic involves direct current electronics while the innovative concerns cutting edge radio frequency techniques. Ham Radio In Plain English

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Technical doctors can dissect the equipment, make amends with many things, and barge into the nuances of radio operations. With the help of some types of software, they can use the Internet along with radios to create hi-tech hybrid systems. Voice and Morse code communication are still the most used routes, but computer-based digital operation is gaining momentum. Today’s popular home station configuration is a hybrid of the computer and radio. The communication can be done between continents. This is one of the intriguing factors of ham radio. Man’s desire to learn is another aspect, which facilitates the progression of this hobby. Age is not a barrier since many familiarize themselves with antennas, propagation of radio waves, solar cycles, sunspots, and similar activities. Antennas have become a real obsession for people who love to invent. New designs are created every day and hams have contributed many new variations to the antenna designer's art. All that is required is some wire, a feed line, and a soldering iron. Hams are also helpful in supporting other areas such as radio control (R/C), model rocketry, and meteorology. Miniature ham radio video transmitters are flown in model aircraft, rockets, and balloons, beaming back pictures from heights of hundreds and even thousands of feet. Ham radio data links also lend a helping hand in the fields of astronomy, aviation, auto racing, and rallies.

Operating a Ham Radio: Making Contacts If you can tune to a radio across the ham bands, you will understand the activities of hams. It can vary from a simple conversation to contesting. Ragchews Hams mostly engage in conversation. This is called “chewing the rag.” Contacts are named ragchews. Ragchews can happen between continents or just across town.


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Nets “Nets” is an abbreviation for networks. They are the organized air meetings, scheduled for hams with similar interests or purposes. Traffic Nets This is the system that passes text messages or traffic, through ham radio. Operators exchange messages, which can range from the mundane to the most urgent.

Emergency Service Nets When disaster strikes, hams who are trained for these purposes organize and provide decisive communications into and out of the affected areas until normality is restored.

ALE Mailboxes and Bulletin Boards ALE is the abbreviation for Automatic Link Establishment. Here a computer system monitors a frequency all the time so that others can connect to it and send or retrieve messages.

Full Duplex Operation Full duplex is a communication mode in which a radio can transmit and receive at the same time by using two different frequencies.

Swap Nets Like flea markets, a weekly swap net allows hams to list items for sale or things they need. A net control station overlooks and moderates the process, and business is generally conducted over the phone once the parties have been put in contact with each other.


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DX-ing, Contests, and Awards DX is short for distance. The thrill of making contacts at a very long distance from home has lured many a ham. Competitions are organized for hams, in which they compete to contact faraway stations and to log contacts with every country. Ham radio contests are events in which one earns points for each contact made. Through these exchanges, hams often contact a specific area, use a certain band, find a special station and try to communicate with as many stations as possible. When two hams make contact, they usually confirm contact by using QSL cards. A ham collects all of the QSL cards received from time to time. Those who make maximum numbers of contacts are given awards in the competitions. Ham fests are often conducted by Amateur Radio Clubs. At a ham fest, one can buy or sell radio equipment and meet people in person after having communicated with them on the air.

Ham Radio and Ordinary Radio Ordinary radio sets are designed to receive either Amplitude Modulated (AM) or Frequency Modulated (FM) broadcast. Ham radio operators use Single Side Band (SSB) transmission for their communication requirements. Ham radio stations use very low power, less than 100 watts. But a broadcast station uses power in the kilowatts range. Many broadcast band radio receivers cover some of the frequencies earmarked for the ham radio stations. A four band radio set usually covers some popular ham radio frequencies like 7 to 7.1 MHz (i.e. 7000 to 7100 kHz), 14 to 14.350 MHz (i.e. 14,000 to 14,350 kHz) and 21 to 21.450 MHz (i.e. 21,000 to 21,450 kHz). This kind of receiver can be improvised to receive ham radio transmissions with very little effort. While hearing ham radio stations in ordinary radio sets, the sound will resemble a duck quacking. Transceiver The term transceiver is used to identify the equipment. Both transmitters and receivers are assembled in one unit to perform two basic roles. The transmitter generates a radio frequency signal of required power at the desired frequency. It should have Ham Radio In Plain English

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some means of changing or modulating the basic frequency, so that it can carry a feasible signal. The receiver must be able to select the required frequency, rejecting all unwanted frequencies. Also, the receiver should have the capacity to amplify the weak incoming signal to prevail over the losses the signal suffers in its journey through space. In a radio receiver, the modulated signal is received after the conversion of the original modulated carrier signal into another carrier modulated by the same modulation waveform but at a much lower frequency. This mixing is done with another locally generated sine wave signal. At the output of the non-linear mixet, the difference frequency, called intermediate frequency, is selected by a tuned circuit. (If this sounds like gobbledygook, don’t worry, keep reading!)

Transceiver

Cost of Equipment An endearing factor for an aspiring ham is that the necessary equipment needed to get started in this field should not cost an arm and a leg. Start up can begin with less than $200. Depending on your pocketbook, you can select a wide range of equipment which varies from $100 to $2,000. You can easily shop from e-shops on the Internet or from some of the ham stores in town.


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Setting Up Ham Radio Equipment

Though there are no special rules regarding the mode of equipment for starting, it’s better to begin with the base station rather than going for mobile or handheld. This way, you will have the opportunity to judge the niceties of a station operation. To start the hobby, a simple short wave radio and a QRP transmitter are all that are required. If everything is available, it will only take a few hours to get set up. Initially, most ham operators begin with a simple station. An HF radio, microphone, Morse code key, and a simple wire dipole antenna are all that are required for your cruise on air. The step by step process is given below. 1. First, locate the place where you are going to keep the equipment. It is better to keep the length of the coaxial cable to a minimum. Take special care while deciding the location, in order to bring the coaxial and ground wire in easily. 2. A desk or computer credenza is a perfect place for the equipment. 3. Install an eight foot copper ground wire into the ground. Lay a heavy wire from the ground rod to the grounding post on the ham radio. 4. Lay an antenna coax from the antenna to the radio shack. 5. Proper clearance should be kept on the rear side of the radio for air circulation. 6. Place an electrical surge protector between the equipment and outlet. 7. Place an antenna lead to a switch enabling the shunting circuit to ground. 8. Cover the radio to protect it from dust.


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Bandwidth Selection The transceiver is equipped with a function key. As you operate the function key, you can select the desired bandwidth. Before you start, take these precautions: 1. Ensure that power supply connections are securely made and proper polarity is available. 2. Make sure that the antennas are connected to the correct pigtails on the transceiver (mostly on the rear). The basic steps required to begin an operation are: 1. Turn the transceiver on. 2. Set the band on which you want to operate. 3. Adjust the volume level of the audio. 4. Adjust the operating frequency.

Some Points for Beginners “Nothing worth knowing can be understood with the mind.” ~ Woody Allen ‘To Listen’ Is the Phrase As in intrapersonal communications, listening is the most powerful and important way for a beginner to start. This way, one can learn the techniques of many hardcore amateurs. Listening to air contacts is called “reading the mail.” There is no secrecy in ham communications - they are open and public. Contacting Your Nearest Club Once you decide to join this hobby, take full advantage of the opportunities it offers. Meet as many people as possible in the nearest club. They will certainly help you.


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Hams often find great joy in helping the beginners. Such people are known as “Elmers.” An Elmer knows the stuff required to pass the test and will often help you to prepare.

Finding One in the Same Boat Find a friend who is just like you, at the bottom of the learning curve. Meet them on air and enjoy the proceedings together. If you do not have a club near you (to take the test or meet an Elmer), contact the ARRL Development office at www.arrl.org/development. They will have the information you need.

Know Your Equipment A lot of equipment is available on the market. Depending on the price, such equipment differs from one another on performance and capabilities. It’s always best to consult with your elmer, regarding the purchase of any advanced equipment. Equipment manuals can assist with the understanding of your instrument. Demos or tutorials are available so do not hesitate to check them out. Keep the manual ready for any quick reference.

Use All Resources Internet forums are available. Just join the forum and you can get many valuable tips. One such help group is http://groups.yahoo.com/group/hamradiohelpgroup/

Practice Courtesy Accustom yourself with the practice of saying polite words like "Please," "Thanks," "Excuse me,” and "Sorry." This way you can earn the goodwill of your cooperators.


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Be Cool Of course, it’s possible that, no one responds to your CQ (general call sent by one station to any other station). Relax and try again. Also some technical hiccups can occur. Through practice you will be able to rectify minor issues. You can almost always get help from your buddies regarding these.

Ham and Phonetics During radio operations, at times the signals may be weak. This makes it difficult for the person to comprehend the words completely. This problem sometimes necessitates hams to spell out certain words, for example, a name. If you try this using the English alphabet, it can cause greater confusion. If you try to spell your name using the letters alone, a listener may misinterpret one letter for another. So instead of spelling out with letters, use words known as phonetics, which have been chosen specially for serving our purpose. The standard alphabet is: Alpha, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliet, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu. There are also some standards for the pronunciation of numbers and numerals. In order to avoid confusion with numbers such as 50 and 15, you have to speak each digit separately. According to standards, you should spell decimal to represent decimal point. If you want to say 15.100 MHz, you should say the words, “one five decimal one zero zero.”

Operation Using Computers The use of computers in ham radio operations have enthused the younger generation. A computer is connected to a terminal node controller and a transceiver for a packet radio operation. The terminal node controller has a modem similar to the modem used for Internet connections. The TNC also utilizes firmware. It is this firmware that


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converts computer data into packets of digital information, which is then sent across the packet radio network. This firmware is called PAD or packet assembler. This unit captures incoming and outgoing data and encapsulates it into packets of data. This data can be sent to and from a data radio or transceiver. The enter key of the keyboard can also function as the push to talk facility in the normal ham radio operation.

Satellites This is an area which excites many hams. There are many small satellites orbiting the earth, which are made and operated by radio amateurs worldwide. AMSAT is the global organization, which organizes satellite construction and lobbies for spare space on commercial launch vehicles. Communication can be made by Morse code, voice, or pocket radio over very large distances with the help of these satellites. The easiest satellites to use are the low orbit ones as they can be availed with low power and modest antennas. Russian RS series and South Africa’s Sunsat (SO-35) are low orbited satellites. As the sensitivity of these satellites is superior, even operation from buses, trains and trams becomes possible! These low orbit satellites have short pass-times and they are quite good for communication up to a few thousand kilometers while the other satellites would require more powerful and bigger antennas. But they offer worldwide communication. Amateur Radio on Boats "My mom said she learned how to swim when someone took her out in the lake and threw her off the boat. I said, 'Mom, they weren't trying to teach you how to swim.'" ~ Paula Poundstone, comedian Amateur radio is quite popular among the yachting and small boat community. It is used to provide general communications and for receiving weather information. However certain restrictions may exist when operating within the territorial limits of another country.


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Hams also operate a lot of “maritime nets" through which information of common interest to mariners, such as weather, is exchanged. Different digital modes like SITOR/ AMTOR, radio teletype (RTTY), PACTOR I, PACTOR II, PACTOR III, PSK31 are normally used. Here’s a quick glance at some of the terms used for propagation on a boat. Pactor -- It is a mode that uses both upper and lower case characters and teleprints over radio with the help of a code. Pactor is a combination of amtor (amateur teleprinting over radio) and packet. Common modes are Pactor I and Pactor II. TNC -- TNC is the short form for terminal node controller. It is comparable to a radio modem. PTT -- PTT stands for push to talk. It is what makes your radio transmit. SOFTWARE -- A type of software is used to make a cruising e-mail work. This is freely available on the Internet. ISP/RADIO E-MAIL PROVIDER -- It is with the help of a radio e-mail provider that actual access takes place.

Signal Reports (the RST code) Signal reports are used for gauging the strength of the receiving signals. Codes as given in the table are utilized for conveying the strength of the signal.

R EADABILITY

SIGNAL STRENGTH

TONE

R1 Unreadable

S1

T1

R2

S2

R3 Readable with difficulty

S3

R4

S4

R5 Perfectly readable

S5

Faint signals

T2 Weak signals Fairly good signals


Rough

T5

Modulated (warble)

T6 Moderately strong signals

S8 S9

T3 T4

S6 S7

Extremely rough

T7

Slight ripple

T8 Extremely strong signals

T9

Pure note

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International Q-Code (Extract) QRG

What is my exact frequency?

QRH

Does my frequency vary?

QRI

What is the tone of my transmission?

QRK

What is the readability of my signals?

QRL

Are you busy?

QRM

Are you being interfered with?

QRN

Are you troubled by static?

QRO

Shall I increase power?

QRP

Shall I decrease power?

QRQ

Shall I send faster?

QRS

Shall I send more slowly?

QRT

Shall I stop sending?

QRU

Have you anything for me?

QRV

Are you ready?

QRX

When will you call me again?

QRZ

Who is calling me?

QSA

What is the strength of my signals?

QSB

Are my signals fading?

QSD

Is my keying defective?

QSL

Can you give me acknowledgment of receipt?

QSO

Can you communicate with..... direct (or by relay) ?

QSP

Will you relay to....?

QSV

Shall I send a series of V's ?

QSY

Shall I change to another frequency?

QSZ

Shall I send each word more than once?

QTH

What is your location?

QTR

What is the correct time?


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Continuous Wave Transmitter The continuous wave is used for the transmission of pulses of RF energy for creating Morse code characters. This type of transmission is also called interrupted continuous wave transmission. The advantage of cw transmission is that it requires a narrow bandwidth and less output power. Even severe noise conditions will not hamper the transmission. A cw transmitter facilitates the transmission with the help of a generator, amplifier, keyer, and antenna. RF oscillations are generated and are then amplified. The oscillator generates the RF carrier at a specified frequency. The oscillator outputs are then amplified many times in order to equip them to radiate over long distances.

Web Sites for Buying Equipment and Electronic Circuits www.hamradio.com www.discountfamilyradios.com www.unadilla.com http://www.advancedspecialties.net http://www.burnabyradio.com http://www.comdac.com http://www.hamtronics.com

Buying Old Equipment ‘Old is gold’ goes the saying. Many people prefer to go for old and used equipment. The following web sites offer details of used ham radio equipment suppliers. http://hometown.aol.co.uk/oldradioparts/front.htm http://www.ac6v.com/components.htm http://archives.radioattic.com/features/started.htm


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The following list provides some of the addresses of old equipment and spare part dealers. They carry a variety of merchandise for collectors and restorers of vintage radio/phono/TV/jukeboxes. Catalogs or inventory lists are available from all of them. Following this list is a directory of commonly needed items, with additional sources:

Antique Electronic Supply 6221 S. Maple Ave Tempe, AZ 85283 Tel: 480-820-5411 Contact Daily Electronics P.O. Box 5029 Compton, CA 90224 Tel: 800-346-6667 (Orders) Tel: 213-774-1255 (Tech) Don Diers 4276 North 50 Street #SC3 Milwaukee, WI 53216-1313 DNF 6690 7 Mile Road South Lyon, MI 48178 Electron Tube Enterprises Box 8311 Essex, VT 05451 Tel: 802-879-1844 Fax: 802-879-7764 Fair Radio Sales Military Surplus Electronics 2395 St Johns Rd PO Box 1105 Lima, OH 45802 Phone: 419-227-6573, 419-223-2196 Fax: 419-227-1313 www.fairradio.com Ham Radio In Plain English

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Kirby 298 West Carmel Drive Carmel, IN 46032

Lippert N61W 15889 Edgemont Meno Fls, WI 53051

New Tube Co. P.O. Box 202 Middle Village, NY 11379 Tel: 718-894-2131

Quest Electronics, Inc. 5715 W. 11th Avenue Denver, CO 80214 303-274-7545 Voice 303-274-2317 Fax [email protected] email Steinmetz Electronics 7519 Maplewood Avenue, Hammond, IN 46324 Tel: 219-931-9316 Michael C. Marx SND Tube Sales 908 Caulks Hill Road St. Charles, MO 63304 Phone 636-939-9190 24 Hour Fax 636-922-0601 E-mail: [email protected]


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Sometimes it happens that one may inherit all of this equipment. But it will not be of any use unless it is fully operational. In such cases, you may be able to get help from the local radio club.

The Statistics of Ham Radio Users “I think there is a world market for maybe five computers.” ~ Thomas Watson, IBM chairman, 1943 Statistics relating to the number of users in the U.S. can be found at: http://www.users.crosspaths.net/wallio/LICENSE.html

Making of a Simple QRP Rig Many free resources are available on the Net for those who want to experience the thrill of making their own QRP rigs. One such site is: http://www.geocities.com/pa2ohh/index.html, which gives a complete explanation for making it very simple. Those who want to go mobile can have a look at http://www.installer.com/pics/instpics.html for more information.


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Chapter 2 Basics of Radio Wave Transmission Mode of Radio Wave Transmission "The wireless music box has no imaginable commercial value. Who would pay for a message sent to nobody in particular?" ~ David Sarnoff's associates in response to his urgings for investment in the radio in the 1920s The electromagnetic energy mainly takes two forms to reach a receiving antenna. It either takes the shape of the ground waves or it navigates as sky waves. Ground waves travel near the surface of the earth. Radio waves that are reflected back to the earth’s surface from the ionosphere are known as sky waves. To put it simply, the surface wave travels along the surface of the earth, while the space wave travels over the surface. A surface wave is not affected by the shape of the land, thanks to the phenomenon of diffraction. As described elsewhere, it takes a bend, when hindered by an obstacle. The surface wave along its journey over the surface induces a voltage in the earth. This causes a loss of energy of the wave. This loss of energy is reduced by polarizing the wave before transmission. The space wave has two ways to reach its destination. The first route is through the direct journey through the air from the transmitting antenna to the receiving antenna. The second way is through the reflection from the ground to the receiving antenna. This is demonstrated in the figure below. As the space wave takes two paths of different lengths reaching the receiving site, there is a possibility that the signal will fade. If the waves reach out of phase, the signal may also fade. On the other hand, if they reach in phase, the signal will be a strong one.

Propagation of VHF Signal VHF and UHF radio signals often travel in straight lines to all possible directions. If there are no obstructions on its path, the signal can travel very long distances. But presence of obstructions may weaken the signals. Since the earth’s surface is curved, there are some limitations for these waves. They will not bend around the curvature of the earth and will get lost in space, due to its propagation in straight lines. Because of Ham Radio In Plain English

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this characteristic, VHF/UHF propagation is described as line of sight propagation. They can travel as far as human eye can see the horizon.

Reflection of VHF/UHF Signals These signals are reflected when they are obstructed by metal objects. Depending upon the area of the objecting surface, the amount of reflection also varies. Large metal objects such as an aircraft or a large metal building reflect these waves significantly. The property of these signals is considered an advantage in large cities, where some other signals would have been blocked.


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The Process of Ionization in the Ionosphere The region of atmosphere that extends from 30 miles to about 250 miles is rightly called ionosphere due to the presence of electrically charged gas atoms called ions. The ultraviolet rays from the sun collide with gas atoms and hurl an electron from the atom. This gives the atom a positive charge and it then coexists with the negative charged free electron in space. This process is known as ionization. The presence of many such free ions and electrons leads to the formation of an ionized layer. An exact reverse happens thereafter, which reinstates the old position again. The positive ion and the electron collide with each other thus giving the old neutral status to the positive ions. Depending upon the time of the day, these combination and recombination processes compete against each other. Whenever the rate of ionization exceeds the recombination process, the density of the ionized layers increases, greatly affecting the radio waves.

"Everything that can be invented has been invented." ~ Charles H. Duell, Commissioner, U.S. Office of Patents, 1899

The Ionosphere Layers The charged particles in the ionosphere create four distinct layers, within the ionosphere. These groups are again classified into two categories. One is present when the earth’s surface is bright and the other in darkness (when the earth’s surface is hidden from the sun). The four layers are F1, F2, E and D. During the night, the two F layers combine to form one layer. The E and D layers are absent during night hours.


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The F Layer Worldwide amateur radiations are possible, thanks to the F layer. As the radio signal strikes this layer, it is bent back at an angle towards the earth without any significant energy loss. The F layer splits into two layers, F1 and F2, during daytime. F1 is the inner one and F2 is the outer one. Much of the refraction during daytime happens in F2 layer.

The E Layer The E layer exists only during the daylight and is found between the F and D layers. At very high frequencies, some refraction occurs in the E layer. As this is sporadic in nature, this phenomenon is known as sporadic-E.


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The D Layer This layer, which is closest to the earth, is found only during daytime. The main characteristic of this layer is that it absorbs both medium and high frequency radio waves instead of refracting them. Sometimes the level of absorption is too large and the communication of radio waves may not happen for a short period. This ionization affects another phenomenon in the ionosphere called refraction. Refraction is affected when there is an abrupt change of velocity of the upper part of the radio wave as it enters a new medium. The factors, such as the frequency of the radio waves, the density of the ionization of the layer, and the angle at which the wave enters the layer, decide the quantum of refraction. The figure depicts the effect of ionization densities on refraction. An ionized layer itself is divided into different regions according to densities. We will dissect the three layers one by one.

As the wave enters the bottom layer, it is entering a region of high degree ionization. The sudden change in the velocity of the upper part causes it to bend towards the earth. At the center portion, as the density of ionization is uniform, the refraction effects Ham Radio In Plain English

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are less. As it again enters the area of lesser density, the wave is bent away from the earth.

Critical Frequency As the wave enters an ionospheric layer, there is a possibility for the wave to get refracted or to get lost in space. For a given layer, there is a maximum frequency at which the radio waves can be transmitted vertically and get returned to earth. This frequency is termed as critical frequency.

The waves with higher frequencies than the critical frequency will be lost in space. From the figure, we can observe that for lower frequencies the waves get refracted more sharply. The highest frequency wave, which is of higher frequency than the critical frequency of the ionized layer, gets lost in space.


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Chapter 3 The Factors Affecting Radio Wave Transmission “640K ought to be enough for anybody.” ~ Bill Gates, 1981 Factors Affecting Radio Waves The radio waves along their journey from the transmitting antenna to the receiving antenna are affected by a lot of factors. Absorption As the radio waves travel through the ionosphere, the current conditions greatly influence the radio waves. The absorption causes a lot of energy drain and makes the signal weak. Absorption occurs predominantly in the region of higher ionization density. The radio waves entering into the ionosphere lose some of their energy to the free electrons and ions. When these ions and free electrons collide with other particles much of the energy is lost into the atmosphere. Fading Another factor that hinders the flow of radio waves is fading. This is due to many conditions. One of them is refraction. Refraction causes polarization of the wave and this in turn causes fading. Absorption of energy in the ionosphere is another reason. The figure below explains the process of multi-path fading.


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Due to various atmospheric properties, radio waves may reach the same destination in different paths. These paths can be ground waves, waves affected due to ionospheric refraction, reflected waves from the ionosphere, and so on. The figure describes the different possibilities by which a radio wave can reach destination A. Here, the end result is that the waves can reach out of phase at the receiver thus causing weak signals. This is known as multi-path fading.

Losses Due to Ground Reflection

If a radio wave along its passage gets reflected from the earth’s surface, then some amount of energy may be lost. Factors such as frequency of the wave and ground irregularities determine the extent of loss.

Free Space Loss When waves are transmitted, the wave front starts spreading out. When the distance of travel increases, the spreading of the wave front also increases. This means Ham Radio In Plain English

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that the amount of energy in a fixed area also reduces. As the wave front reaches the receiving antenna, only a small area of the wave front is covered by the antenna.

Electromagnetic Interference The electromagnetic interferences also can create havoc in radio communications. These are due to either man made interference or natural interference. Man made interference can happen from a variety of reasons. Some are related to devices, which generate radio frequency energy. The extent of man made interference may vary largely throughout the day and may be reduced at night. If a lot of devices are used in areas such as industrial estates, the signals absorbed by a receiver at that particular location may become very feeble. Natural interferences are caused by natural phenomena, such as thunderstorms, cosmic sources, snowstorms, and the sun. All of these can cause energy radiations and may propagate almost in manner similar to radio waves. The reception of these radiations in the receiving antenna can cause distraction to the radio waves. As this does not affect above the frequency of 30 MHz, this will have little effect on amateur bands. The electromagnetic interference can be controlled or eliminated by various methods such as the use of directional antennas.

Radio Waves and Weather Weather changes can affect the radio propagation to a certain extent by leading to the weakening or attenuation of the radio waves. Raindrops are capable of absorbing some power from the radio waves and this power is then scattered away in the form of heat. Fog can also cause problems to the radio waves. Fog is suspended in the atmosphere. The amount of water per unit volume determines the quantum of hindrance caused by the fog.

Ducting Normally, warm air is found near the surface of the earth. As the altitude increases, the air becomes cooler. Sometimes an abnormal situation occurs, as a layer of Ham Radio In Plain English

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warm air is formed above the layers of cool air. This is referred to as temperature inversion. This results in the formation of channels or ducts of cool air between the surface of warm air and earth or between two layers of warm air. These ducts trap the radio waves (which would otherwise bleed out into space) and guide them along the surface of the earth. This process is known as ducting. When this happens, the radio waves will travel more distance than usual.

Earth Moon Earth Earth Moon Earth or EME is a fascinating part of amateur radio communications. Through this process a ham attempts to direct the signal towards the moon so that a fellow ham can receive the moon- echoes. In order to make this happen, one must have very sensitive equipment with powered amplifiers and a large antenna system. This is because the echoes become extremely feeble. The process is known as path loss.

Satellite One can communicate with another station through a satellite, if both the stations are in the view of the satellite at the same time. When the satellite is low to the horizon, the required power will be higher as the distance to the satellite is very large.

Sunspots The sunspot cycle is a phenomenon that extends to a period of 11 years. Every five and half years, the sun reaches a low in sunspots and during the next five and a half years the sun’s surface is dotted with hundreds of spots. When the number of sunspots increases, the quantum of solar energy increases, thus making the ionosphere heavily charged. During this period, when the number of sunspots is high, the HF propagation also improves.


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Chapter 4 Transmission Theory “Success always occurs in private, and failure in full view.” ~ Anonymous Transfer of Radio Waves from the Transmitter to the Antenna

The energy waves from the transmitter cannot be carried using the ordinary electrical wire without energy loss. Transmission lines are used for this purpose. As the antennas are normally located a distance from the instrument, the transmission lines are necessary for carrying the energy from the radio room to the antenna. The transmission line has two ends. The end connected to the transmitter or the source is called the input end. The end connected to the antenna is called the output end. Transmission lines are mainly categorized into two types, balanced and unbalanced lines. Balanced lines consist of two parallel wires each capable of carrying radio waves. The unbalanced lines have only one wire to carry the signals. The advantage of the coaxial line is that it matches the impedance of most commercially made ham radios. Also, there is no problem in placing the cables near metal objects due to the presence of the shield around the wire. Ham Radio In Plain English

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The transmission line can also be expressed in terms of its impedance. Input impedance is the ratio of voltage to the current at the input end. This impedance is contributed to the transmitter by the transmission line and antenna. The ratio of voltage to the current at the output end is known as output impedance. This impedance is contributed to the load by the transmission line and its source. Transmission Line Theory The electrical properties of two-wire transmission lines are mostly influenced by the construction of the line. The two-wire line functions like a long capacitor. Since long conductors also possess a magnetic field around them, they show the properties of inductance. The inductive and capacitive reactance depends on the applied frequency. A conductance value also may be present, which is the value of the current flow that is expected through the insulation. Lumped Constants A transmission line also exhibits the properties of inductance, capacitance, and resistance just like the ordinary circuits. In practice, the constants in conventional circuits are lumped into a single device or component. For example, two metal plates separated by a small space can be used to supply the required capacitance for a circuit. Similarly a coil of wire has the property of inductance. Considering the ideal case, a transmission line would also have its constants of inductance, capacitance, and resistance lumped together, as shown in the figure.

But in practice, this is not the case. Transmission line constants are distributed. Ham Radio In Plain English

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Distributed Constants The distributed constants in the transmission lines are spread along the entire length of the transmission line and cannot be distinguished separately. Factors like the length of the line, the size of the conducting wires, the spacing between the wires, and the dielectric (air or insulating medium) between the wires determines the amount of inductance, capacitance, and resistance in the line.

Inductance of a Transmission Line The flow of current through a wire induces some magnetic lines of force in the wire. The change in the value of the amplitude of the current induces a change in the field also. This produces a certain amount of inductance, which is expressed in micro Henry per unit length.


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Capacitance of a Transmission Line Capacitance is also present in between the transmission line wires. The two parallel wires function as the plates of a capacitor and the air between them acts as a dielectric. The electric field thus formed between the wires is similar to the field that exists between the two plates of a capacitor.

Resistance of a Transmission Line As shown above, the transmission line has electrical resistance along its length. This resistance is expressed in ohms per unit length.


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DC Applied to a Transmission Line

In the above figure, a battery is connected to a load through a transmission line. When the switch is open, both current and voltage become nonexistent on the line. As the switch is closed, point A becomes positive and point B becomes negative. This potential difference soon migrates to A’ and B’. This causes an electric field as well as a magnetic field. The moving electric field and the accompanying magnetic field together constitute an electromagnetic wave that is moving from the generator (battery) toward the load. This energy that reaches the load is equal to that developed at the battery.


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AC Applied to a Transmission Line

The figure above explains how the things will change when an ac generator replaces a battery. The instantaneous values of the generated voltage are propagated to the other end, one after the other. Here the difference is that the applied voltage is sinusoidal, not a constant one.


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Chapter 5 Antenna “If you can’t beat your computer at chess, try kickboxing.” ~ Anonymous Antennas An antenna is a vital ingredient in any radio transmission system. RF signals produced by a transmitter should be transferred to the space for a successful transmission. The device used for this purpose is known as antenna. A transmitting antenna sends the signal into space, which is later absorbed by a receiving antenna. The transmission of RF energy is done in the form of electromagnetic field. The receiving antenna absorbs the electromagnetic field and voltage is induced in the antenna. The receiver then converts this electromagnetic radiation back into RF energy.


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The Basic Antenna Antennas hold a vital place in radio communication. An antenna consists of a conductor or a set of conductors, which either radiates or collects electromagnetic energy. A radio frequency energy produced by a transmitter is carried to an antenna through a transmission line. The antenna transforms this energy into radio waves that propagate in space at the speed of the light. This wave continues to travel until it is either reflected or absorbed by an object. If the obstructing object is another antenna, it absorbs part of the radio waves and transforms it into energy. This energy is carried away to a receiver through another transmission line. The basic components of a communication system are: 1) Transmitting equipment 2) Transmission line 3) Transmitting antenna 4) Medium 5) Receiving antenna 6) Receiving equipment The two basic fields associated with every antenna are induction field and radiation field. The induction field, which is the field related with the energy stored in the antenna, has no hand in the transmission of electromagnetic energy, although radiation of energy is not possible without the induction field. Antennas are basically classified into two types. They are Hertz antennas and Marconi antennas. Hertz antennas are generally located at a distance above the ground and are capable of radiating vertically and horizontally. Marconi antennas are located perpendicular to Earth, one end of it being grounded. While Hertz antennas are used for frequencies above 2 MHz, Marconi antennas are used for frequencies below 2 MHz. The main parts of an antenna are the coupling device, the feeder, and the antenna. The transmitters and feeders are connected using the coupling device. The transmission line that caries the energy to the antenna is known as the feeder. The characteristic Ham Radio In Plain English

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of the antenna depends on the frequency of the transmitting operation, the amount of the power to be radiated, and the direction of the receiving set.

Energy Distribution on an Antenna Electromagnetic radiation is based on two laws. First, a moving electric field creates a magnetic field. The second is that a moving magnetic field creates an electric field. At any moment, these two fields will be perpendicular to each other. A high-frequency generator is attached to a half cut wire. The set frequency of the generator is such that each half of the wire is one-fourth the wavelength of the output. The system thus produced is known as a dipole, which is a common type of antenna. At a given instant, the left side of the generator is negative and the right side is positive. As a result, the electrons will flow away from the negative terminal and will be attracted to the positive terminal. The amplitude of the flowing current will be varying with the generated voltage. The charge distribution will be of sine wave pattern. After every half cycle, the polarity of the charges will be reversed. The sinusoidal variation of charge lags the sinusoidal variation of the current by one-fourth the cycle. Radio Wave Modulation The functioning of a radio may be a perplexing thing to a beginner. Your voice produced in front of a microphone is heard using another radio, which is placed at a different location. How does this happen? Modulation is the process of merging a radio signal with an information signal. That means that for modulation to happen a carrier must be there. It is this carrier signal that delivers this information to the desired destination.

Morse Code Modulation Morse code turns off and on an RF carrier in order to transmit a simple code alphabet. This is also known as continuous wave (CW).


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Radiation of Electromagnetic Energy The E field and the H field of an electromagnetic energy will be 90 degrees out of phase with each other. As the energy wave traverses a greater distance, the energy spreads out over a greater area and decreases as the distance traversed increases. Consider that an alternating current is applied at the starting point X of a wire, which extends up to Y. The wave will pass through the wire until point Y. The end Y is free and because of that the wave is unable to travel further. This wave will then reflect back and travel to the starting point. Here also, it gets reflected and the process repeats. As this to and fro motion continues, the energy of the wave will be gradually lost by the resistance of the wire. But each time when it reaches the starting point X, the lost energy will be reinforced. This results in the continuous oscillation of energy along the wire. These oscillations are then applied to the antenna at a rate equivalent to the frequency of the f voltage. The waves travel at a rate of 300,000,000 meters per second. The antenna length should be made in such a way that one to and fro motion of the wave should happen during one cycle of the RF voltage. The maximum movement of electrons always happens at the center of the antenna. Due to this, the center of the antenna is always at low impedance and this condition is called the standing wave of the current. The points having high current and voltage are called as current and voltage loops. The point of minimum current and voltage is called as Nodes.


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Antenna Gain Most of the antennas are highly directional. This means that more energy is radiated in certain directions compared to other directions.


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Antenna Reciprocity As we have already described at the transmitting stage, electrical energy is converted into the electromagnetic energy and consequently radiated into space. At the receiving antenna, electromagnetic energy is converted into electrical energy. The same antenna can be used in both the cases without any loss of efficiency. This property of the interchangeability of the antenna for both transmitting and receiving is known as antenna reciprocity.

Radiation Resistance Radiated energy is lost in heating the antenna wire. Considering radiation, if the assumed resistance is actually present, it would dissipate the same quantity of power the antenna takes to radiate the energy. This assumed resistance is named as radiation resistance.

Isotropic Radiation Some of the antennas radiate equal amount of energy in all directions. This type of radiation is known as isotropic radiation. This is often compared to the radiation pattern from the sun. Sun radiates equal amounts of energy in all directions.

Anisotropic Radiation Radiations produced by most radiators can be found to have higher intensity in one direction. These types of radiators are referred to as anisotropic radiators. The ordinary flashlight is the best example of an anisotropic radiator.

Antenna Loading The same antenna system can be used for transmitting and receiving signals having different frequencies. For this to happen, the antenna should either be physically Ham Radio In Plain English

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or electrically lengthened or shortened. Making physical changes are not that practical. That necessitates the reduction or enlargement of the electrical length. This is done by inserting either a capacitor or an inductor in series with the antenna. The process is known as loading.

“Work is a necessary evil to be avoided.” ~ Mark Twain, writer

Antenna Positioning Special care should be taken to locate the antenna well above the ground keeping it away from any tall buildings, trees, electrical power conductors, telephone and telegraph wires, and other metal objects that will absorb the energy. Better results can be obtained by hoisting it to the maximum possible height. The antenna and the output stage of the transmitter have certain impedance in them. Maximum possible energy transfer from a source to the load is possible only when the impedance is matched. That means that the output impedance of the transmitter should match the input impedance of the antenna. A co-axial cable is used by most amateurs because of its properties of maximum efficiency and minimum loss of energy. RG-59/U is a small co-axial cable having an impedance of 73 Ohms. Ham Radio In Plain English

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Other stations often judge the performance of an amateur station from the strength of the signal they hear. This enunciates the importance of an effective antenna system.

Types of Different Antennas

Most of us have a misconception that if the length of antenna is more, than the energy radiated by it will also be on the higher. But this is not the case. Antenna should have specific dimensions for effective operation. The basic Hertz antenna has a length of half its wavelength. This is also called as a dipole or a doublet. The basic Marconi antenna has a length one-fourth its wavelength. Half–wave Antennas


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A half-wave antenna (Hertz, dipole or doublet) is made up of two lengths of tubing, each having one-fourth of wavelength at a particular frequency. This antenna is capable of operating at a distance above the ground surface. For a half-wave antenna, the current is maximum at the center and minimum at the ends. Voltage is minimum at the center and maximum at the ends.

Quarter–wave Antennas A grounded quarter-wave antenna can be obtained by cutting a half-wave antenna and then grounding one end well. The antenna thus obtained will resonate with the same frequency as the ungrounded half wavelength antenna. Most of the mobile transmitting and receiving antennas are quarter-wave (Marconi) antennas.

Horizontal Dipole The beginners often start with this antenna, as it is easy to construct. It gives excellent results in H.F bands. The most attractive thing is that it requires only two points to hook it up. The height can be above 30 feet, and the higher the better. This is considered a basic antenna. The length in feet is calculated using the formula, 468/f MHz. An insulator is used in the center after cutting it into two halves. The maximum radiation is in the broadside of the axis and least along the axis line. The materials of the dipole are easily available. Dipole can be used for both local as well as Dx. Inverted V The difference between the inverted V and the dipole is that the center is raised to a height comparing with the ends. The length of the inverted V in feet can be calculated using the formula, 464/f MHz. The angle between two halves must be between 90 and 120 degrees. The radiating part of a vertical antenna is called the radiator. Normally copper wire or aluminum tubing is used for the radiator. Ham Radio In Plain English

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“If it’s the Psychic Network, why do they need a phone number?” ~ Robin Williams, comedian Folded Dipole A folded dipole is similar to an ordinary half-wave antenna with one or more additional conductors connected across its ends. Additional conductors are placed at a distance which will be equal to a fraction of its wavelength. The spacings are materialized using standard feed-line spreaders. The folded dipole is used over a wider frequency range than that of a simple dipole.

Directional Antennas


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A directional antenna focuses or directs radio energy in a specific direction. As a result of this the stations on the directed sides will be getting strong signals when compared to those on the opposite sides. That means that the directional antenna propagates the energy more in one direction at the cost of a weak radiation on the rear side.

Parasitic Antenna The parasitic antennas are defined as the antennas, in which the radio energy is obtained in some elements by the induction or radiation from the driven element. Directional antennas are example of the parasitic antenna. Yagi and quad fall under this category.

Yagi Antenna Yagi antenna consists of many dipoles, one shorter from the other. Refer to the figure given below. Reflectors, radiators, and directors are the parts of a yagi antenna. The elements are not placed uniformly thus causing an uneven spacing between the elements. The reflector and director are usually found welded to a conducting tube. The radiations from different elements will be in phase in the forward direction, but may not be in phase in other directions. A higher number of parasitic elements guarantees more gain, but may lead to a narrow frequency response.


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One Antenna for Different Bands You can make an antenna for different bands. Those who are interested in making antennas for all bands can locate resources on the web. •

To build a sturba curtain antenna for all bands, visit this page: http://www.hamuniverse.com/sturba.html

•

The following url contains a detailed study to use a patch array for different bandwidths with varied patch lengths and a low loss PCB material: http://www.itn.liu.se/~shago/Publications/UWB_antenna.pdf A lot of resources on quad antennas are available at

http://www.dxzone.com/catalog/ Technical_Reference/Antennas/Quad/ - 30k http://members.fortunecity.com/xe1bef/10meters-antenna.htm


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Terminology Used in Array Antennas Driven Element A driven element is the element connected directly to the transmission line. It is almost similar to the dipole. While transmitting, it receives the power directly from the transmitter. Similarly, while receiving, it delivers the absorbed energy directly to the receiver.

Parasitic Element A parasitic element is placed near the driven element, from which it derives the power. When a parasitic element produces maximum energy radiation in a direction away from itself but towards a parasitic element, it is called a reflector.

Driven Array When all the elements in an array are driven, it is referred to as a driven array.

Bi-directional Array A bi-directional array directs in the opposite directions along the line of maximum radiation.

Unidirectional Array A unidirectional array directs only in one direction.


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Chapter 6

Ham Radio License “Never go to a doctor whose office plants have died.” ~ Erma Bombeck, author FCC The FCC regulates amateur radio under the jurisdiction of the United States of America. This agency can impose fines or even take away licenses if someone is not following the rules. Licenses are required due to many security aspects involved in radio communications.

Control Operator An amateur station is the place where a station facilitated for the amateur radio transmissions is located. A licensed amateur who is completely responsible for the station transmissions is called a control operator.

Amateur Radio License Any individual who intends to operate a ham radio station in the U.S, should hold a license from the FCC, prior to his or her initiation to the world of ham radio. The license is renewed every 10 years. Where can you find the information you’d need to study for the test? Most of the information is right here in this book.

License Classes Just as there is no one driver’s license, amateur radio also has different types of licenses. The FCC has three license classes. One should begin with a technician class


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operator license and then graduate to higher classes. There is no possibility of starting out in a higher class. Naturally, lower classes offer fewer privileges than higher ones. Type of Classes

Offered Privileges

Eligibility Requirements

Technician Class

Have full liberty to use VHF and UHF spectrum 30 MHz.

Passing a 35 question exam is mandatory.

Technician with Morse

Limited privileges in Morse code and voice in the HF spectrum.

A five wpm Morse code exam and a passing grade in the previous exam.

General Class

Limited access to all the HF amateur bands with Morse code, data and voice modes.

A 35 question exam (requires that you have passed the technician and Morse code exams already).

Amateur

Full amateur privileges.

Possess a general class license and

Code

Extra

pass a 50 question exam.

Renewal of the License A license is valid for 10 years. After the 10 years, a further two years are allowed for renewal although the amateur radio privileges cease to exist during this period. After the renewal of the license, one can operate a station. According to the FCC, it is best to renew the license 90 days prior to the expiration date.

Changes Made by the FCC in 2000 The FCC made changes based on three aspects. The number of operator licenses was reduced from six to three. The number of telegraphy examination elements was reduced from three to one. The number of elements in the written examination was reduced from five to three. There will be only one Morse code examination at a speed of five words-per-minute (wpm). RACES station licenses were eliminated.


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Novices and Advanced Class licensees can still operate without any difficulty. New Novice and Advanced Class licenses have not been issued since April 15, 2000. All six license classes will still remain in the FCC database. However, the Novice, Tech Plus, and Advanced Class will gradually cease as members renew or upgrade. The Tech Plus operators can have their licenses renewed under Technician, but they retain the exam credit indefinitely for the five words-per-minute Morse code. Generally speaking, all previous Novice operators and Technician Class operators (licensed before February 14, 1991), even those with long-expired licenses, retain credit for the five wpm Morse code exam. The importance of Morse code is greatly reduced. The top speed in ham radio becomes five wpm. None of the amateur license classes receive any additional frequency privileges and no one lost privileges. The only exception is that Technician Class radio amateurs licensed before March 21, 1987 could become General Class licensees after April 15, 2000 without further examination. A time may come soon, where Morse code is considered obsolete.

Expired License If the time duration after the expiry of the license is less than two years, the license only needs to be renewed. The name, address and call sign of every amateur remains in the FCC's database for a two year "grace period" beyond expiration. In case the two year "grace period" is up, one must start all over again. There are two exceptions to this rule that apply only to Technical Class operators. These exceptions are: One can retain credit for the Element 1 (5 wpm) telegraphy and Element 3 (general written) examination if he/she has an expired FCC issued Technician Class operator license granted before March 21, 1987. That means, even though the license has expired 10 years ago, the person still gets credit for Element 1 and 3. He or she would merely have to pass Element 2 (Technician) and submit the expired Technician license granted before March 21, 1987 (or other evidence) to the VE team to become a General Class operator. Ham Radio In Plain English

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One can retain credit for the Element 1 (5 wpm) telegraphy examination if he/she has an expired FCC issued Technician Class operator license granted before February 14, 1991 or an expired Novice Class operator license issued at any time. But one question remains unanswered. What is the necessity of a license at all? CB radio operators are not required to have one. The simple answer is that ham operators can work at a power level of almost 375 times than that of a CB operator. Also, ham operators can transmit across state and international barriers. This makes it mandatory to understand the international rules and regulations.

VHF/UHF Bands “If it weren’t for Philo T. Farnsworth, inventor of television, we’d still be eating frozen radio dinners.” ~ Johnny Carson, comedian The bandwidth assigned to a ham may differ in some respects from one country to another. This is done by the concerned body of the particular country (like FCC for the U.S.) by going through a lot of aspects. This makes it impossible to have a common frequency allotment in the international level. A technician with no Morse code license can operate on allowed frequency segments above 30 MHz. Most of the activity pertaining to this segment will be limited to local areas. The amateur bands that can be used by a no code technician are given below. Note that the 13 cm band is divided into two segments.

50.0MHz_____________________54.0MHz

6 Meter Band VHF

144.0MHz___________________148.0MHz

2 Meter Band VHF

222.0MHz___________________225.0MHz

1.25 Meter Band VHF

420.0MHz___________________450.0MHz

70 centimeter Band UHF

902MHz______________________928MHz


1240MHz____________________1300MHz


2300~2310MHz_________ 2390~2450MHz



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The Technician with Morse Code HF Amateur Bands

3675kHz___________________ __3750kHz

80 Meter Band HF

7.1MHz______________________7.150MHz

40 Meter Band HF

21.100MHz__________________21.200MHz

15 Meter Band HF

28.100MHz__________________28.500MHz

10 Meter Band HF

VHF Bands

6m

50.0 - 50.1 MHz

CW only

6m

50.1 - 54.0 MHz

Phone emissions permitted, FM included

2m

144.0 - 144.1 MHz

CW only

2m

144.1 - 148.0 MHz

Phone permitted, FM included.

Image Transmissions Image transmissions are the transmissions of still images or that of video images. Fax and slow and fast scan television are some of the image transmission modes. Hams often involve themselves in sharing their personal videos.

Station Licensee If an individual is licensed and owns a radio, then he/she is the control operator when he/she is using the radio. The location where the control operator functions is called the control point. It is possible that the station licensee and the control operator are two separate individuals. A control operator can be anyone who the station licensee designates.


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Identification Call sign is a sequence of letters and numbers the FCC provides for identifying a station. This will be provided as soon as one is licensed. Call sign is a must for ham radio operation. It is mandatory for an operator to identify his or her station every 10 minutes or at the end of the operation. Third Party Communications As implied by the name, third party communications are the communications sent between two amateur stations on the behalf of someone. A third party is the one who has sent the message through two amateur stations. The policy of the FCC states that an amateur should never be paid for third party communications. When one allows a third party to use his/her station, then he/she must closely monitor the transmission. Third party messages to a foreign country can only be made if the U.S. has a third party agreement with that government.

Frequency Sharing Sometimes, it is possible that there are others in the same band. At certain instances, the amateur radio operators share the band with other radio services. When amateurs are the secondary users of a band, one must not interfere with the primary users of the band. This rule stands good for the fellow operators as well.

Power Limits FCC has specified maximum possible power levels. The term coined for this purpose is Peak Envelope Power or PEP. The maximum power output for technician grade is 1500 watts PEP. Maximum power output allowed to a technician with Morse code is 200 watts PEP. One should always use the minimum required power. For example, if only a certain amount of power is required for transmitting to a particular area, then do not use more than the required power, because it is unnecessary wastage.


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Language Any language is permitted. There are many individuals who transmit in other languages like Japanese and Spanish.

Beacons Beacons are special transmitters that work 24 hours a day to give information on radio conditions and propagation characteristics. One must tune to a beacon frequency and check whether a beacon signal is present. The presence of the signal confirms the existence of a radio communication path between the location and the beacon.

Distress Whenever there is a distress call on the radio, contact the person and the proper authorities. It does not matter if the frequency is outside your license privileges. MAYDAY and SOS are the words transmitted in case of an emergency. This should be used for life or property threatening emergencies.

Transmission and Dummy Load During repair, it may be required to operate the station for a while for the correct diagnosis of the problem. Rather than using a live signal, technicians use a dummy load around the antenna. A dummy load is nothing but a huge resistor which has the ability to dissipate the radio signal as heat into the air.

Repeaters As described earlier, most VHF-UHF bands have a line of sight transmission. Due to this, VHF signals are easily blocked by mountains and hills. In order to avoid this situation, a device known as a repeater is used to strengthen the signal. The significance of repeaters is that they make it possible to transmit signals to very long dis-


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tances. The difference between the input and the output of a repeater is termed as offset.

The main rules pertaining to the amateur radio transmission are given below. Not knowing the rules is no excuse. “My father hated radio and could not wait for television to be invented so that he could hate that, too.” ~ Peter De Vries, novelist S 97.5 Station License Required The person having physical control of the station apparatus must have been granted a station license (detailed below) or hold an unexpired document (detailed below) before the station may transmit on any amateur service frequency from any place that is: •

Within 50 km of the Earth's surface and at a place where the amateur service is regulated by the FCC.

•

Within 50 km of the Earth's surface and aboard any vessel or craft that is documented or registered in the United States.

•

More than 50 km above the Earth's surface aboard any craft that is documented or registered in the United States.

The types of station licenses are: •

An operator/primary station license. One, but only one, operator/primary station license is granted to each person who is qualified to be an amateur operator. The primary station license is granted together with the amateur operator license. Except for a representative of a foreign government, any person who qualifies by examination is eligible to apply for an operator/primary station license. The operator/primary station license document is printed on FCC Form 660.


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•

A club station license. A club station license is granted only to the person who is the license trustee designated by an officer of the club. The trustee must be a person who has been granted an Amateur Extra, Advanced, General, Technician Plus, or Technician operator license. The club must be composed of at least two persons and must have a name, a document of organization, management, and a primary purpose devoted to amateur service activities consistent with this Part. The club station license document is printed on FCC Form 660.

•

A military recreation station license. A military recreation station license is granted only to the person who is the license custodian designated by the official in charge of the United States military recreational premises where the station is situated. The person must not be a representative of a foreign government. The person need not have been granted an amateur operator license. The military recreation station license document is printed on FCC Form 660.

•

A RACES station license. A RACES station license is granted only to the person who is the license custodian designated by the official responsible for the governmental agency served by that civil defense organization. The custodian must be the civil defense official responsible for coordination of all civil defense activities in the area concerned. The custodian must not be a representative of a foreign government. The custodian need not have been granted an amateur operator license. The RACES station license document is printed on FCC Form 660.

The types of documents are: •

A reciprocal permit for alien amateur licensee (FCC Form 610-AL) issued to the person by the FCC.

•

An amateur service license issued to the person by the Government of Canada. The person must be a Canadian citizen.

•

A person who has been granted a station license of the type listed above or who holds an unexpired document of the type listed above is authorized to use,


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in accordance with the FCC Rules, all transmitting apparatus under the physical control of the station licensee at points where the amateur service is regulated by the FCC.

S 97.7 Control Operator Required When transmitting, each amateur station must have a control operator. The control operator must be a person who has been granted an amateur operator/primary station license, or who holds an unexpired document of the following types: •

A reciprocal permit for alien amateur licensee (FCC Form 610-AL) issued to the person by the FCC.

•

An amateur service license issued to the person by the Government of Canada. The person must be a Canadian citizen.

“Maybe this world is another planet’s Hell.” ~ Aldous Huxley, writer S 97.9 Operator License The classes of amateur operator licenses are: Novice, Technician, Technician Plus (until such licenses expire, a Technician Class license granted before February 14, 1991, is considered a Technician Plus Class license), General, Advanced, and Amateur Extra. A person who has been granted an operator license is authorized to be the control operator of an amateur station with the privileges of the operator class specified on the license. A person who has been granted an operator license of Novice, Technician, Technician Plus, General, or Advanced class and who has properly submitted to the administering VEs an application document, FCC Form 610, for an operator license of a higher class, and who holds a CSCE indicating that the person has completed the necessary examinations within the previous 365 days, is authorized to exercise the rights and privileges of the higher operator class until final disposition of the application or until 365 days following the passing of the examination, whichever comes first.


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S 97.11 Stations aboard Ships or Aircraft The installation and operation of an amateur station on a ship or aircraft must be approved by the master of the ship or pilot in command of the aircraft. The station must be separate from and independent of all other radio apparatus installed on the ship or aircraft, except a common antenna may be shared with a voluntary ship radio installation. The station's transmissions must not cause interference to any other apparatus installed on the ship or aircraft. The station must not constitute a hazard to the safety of life or property. For a station aboard an aircraft, the apparatus shall not be operated while the aircraft is operating under Instrument Flight Rules, as defined by the FAA, unless the station has been found to comply with all applicable FAA Rules. S 97.13 Restrictions on Station Locations Before placing an amateur station on land of environmental importance or that is significant in American history, architecture or culture, the licensee may be required to take certain actions prescribed by S 1.1301 - 1.1319 of the FCC Rules. A station within 1600 m (1 mile) of an FCC monitoring facility must protect that facility from harmful interference. Failure to do so could result in imposition of operating restrictions upon the amateur station by an EIC pursuant to S 97.121 of this Part. Geographical coordinates of the facilities that require protection are listed in Section 0.121(c) of the FCC Rules. 97.15 Station Antenna Structures Unless the amateur station licensee has received prior approval from the FCC, no antenna structure, including the radiating elements, tower, supports, and all appurtenances, may be higher than 61 m (200 feet) above ground level at its site. Unless the amateur station licensee has received prior approval from the FCC, no antenna structure, at an airport or heliport that is available for public use and is listed in the airport directory of the current Airman's Information Manual or in either the Alaska Ham Radio In Plain English

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or Pacific Airman's Guide and Chart Supplement; or at an airport or heliport under construction that is the subject of a notice or proposal on file with the FAA, and except for military airports, it is clearly indicated that the airport will be available for public use; or at an airport or heliport that is operated by the armed forces of the United States; or at a place near any of these airports or heliports, may be higher than: •

One meter above the airport elevation for each 100 m from the nearest runway longer than 1 km within 6.1 km of the antenna structure.

•

Two meters above the airport elevation for each 100 m from the nearest runway shorter than 1 km within 3.1 km of the antenna structure.

•

Four meters above the airport elevation for each 100 m from the nearest landing pad within 1.5 km of the antenna structure.

An amateur station antenna structure no higher than 6.1 m (20 feet) above ground level at its site or no higher than 6.1 m above any natural object or existing manmade structure, other than an antenna structure, is exempt from the requirements of this section. Further details as to whether an aeronautical study and/or obstruction marking and lighting may be required, and specifications for obstruction marking and lighting, are contained in Part 17 of the FCC Rules, Construction, Marking, and Lighting of Antenna Structures. To request approval to place an antenna structure higher than the limits specified here, the licensee must notify the FAA on FAA Form 7460-1 and the FCC on FCC Form 854. Except as otherwise provided herein, a station antenna structure may be erected at heights and dimensions sufficient to accommodate amateur service communications. [State and local regulation of a station antenna structure must not preclude amateur service communications. Rather, it must reasonably accommodate such communications and must constitute the minimum practicable regulation to accomplish the state or local authority's legitimate purpose. See PRB-1, 101 FCC 2d 952 (1985) for details.]


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S 97.17 Application for New License or Reciprocal Permit for Alien Amateur Licensee (a) Any qualified person is eligible to apply for an amateur service license. (b) Each application for a new amateur service license must be made on the proper document: •

FCC Form 610 for a new operator/primary station license.

•

FCC Form 610-A for a reciprocal permit for alien amateur licensee.

•

FCC Form 610-B for a new amateur service club or military recreation station license.

(c) Each application for a new operator/primary station license must be submitted to the VEs administering the qualifying examination. (d) Any eligible person may apply for a reciprocal permit for alien amateur licensee. The application document, FCC Form 610-A, must be submitted to the FCC, 1270 Fairfield Road, Gettysburg, PA 17325-7245. (1) The person must be a citizen of a country with which the United States has arrangements to grant reciprocal operating permits to visiting alien amateur operators is eligible to apply for reciprocal permit for alien amateur licensee. (2) The person must be a citizen of the same country that issued the amateur service license. (3) No person who is a citizen of the United States, regardless of any other citizenship also held, is eligible for a reciprocal permit for alien amateur licensee. (4) No person who has been granted an amateur operator license is eligible for a reciprocal permit for alien amateur licensee. (e) No person shall obtain or attempt to obtain, or assist another person to obtain or attempt to obtain, an amateur service license or reciprocal permit for alien amateur licensee by fraudulent means. (f) One unique call sign will be shown on the license of each new primary station. The call sign will be selected by the sequential call sign system. Ham Radio In Plain English

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(g) No new license for a club, military recreation, or RACES station will be granted. “Television enables you to be entertained in your home by people you wouldn’t have in your home. ~ David Frost, talk show host

S 97.21 Application for a Modified or Renewed License (a) A person who has been granted an amateur station license that has not expired: (1) Must apply for a modification of the license as necessary to show the correct mailing address, licensee name, club name, license trustee name, or license custodian name. The application document must be submitted to: FCC, 1270 Fairfield Road, Gettysburg, PA 17325-7245. For an operator/primary station license, the application must be made on FCC Form 610. For a club, military recreation, or RACES station license, the application must be made on FCC Form 610-B. (2) May apply for a modification of the license to show a higher operator class. The application must be made on FCC Form 610 and must be submitted to the VEs administering the qualifying examination. (3) May apply for renewal of the license for another term. (The FCC may mail to the licensee a FCC Form 610-R that may be used for this purpose.) The application may be made on the FCC Form 610-R if it is received from the FCC. If the Form 610-R is not received from the FCC at least 30 days before the expiration of the license, for an operator/primary station license, the application may be made on FCC Form 610. For a club, military recreation, or RACES station license, the application may be made on FCC Form 610-B. The application must be submitted no more than 90 days before its expiration to: FCC, 1270 Fairfield Road, Gettysburg, PA 17325-7245. When the application for renewal of the license has been received by the FCC at 1270 Fairfield Road, Gettysburg, PA 17325-7245 prior to the license expiration date, the license operating authority is continued until the final disposition of the application. (4) May apply for a modification of the license to show a different call sign selected by the sequential call sign system. The application document must be submitted to: FCC, Ham Radio In Plain English

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1270 Fairfield Road, Gettysburg, PA 17325-7245. The application must be made on FCC Form 610. This modification is not available to club, military recreation, or RACES stations. (b) A person who had been granted an amateur station license, but the license has expired, may apply for renewal of the license for another term during a two year filing grace period. The application document must be received by the FCC at 1270 Fairfield Road, Gettysburg, PA 17325-7245 prior to the end of the grace period. For an operator/primary station license, the application must be made on FCC Form 610. For a club, military recreation, or RACES station license, the application must be made on FCC Form 610-B. Unless and until the license is renewed, no privileges in the Part are conferred. (c) Each application for a modified or renewed amateur service license must be accompanied by a photocopy (or the original) of the license document unless an application for renewal using FCC Form 610-R is being made, or unless the original document has been lost, mutilated or destroyed. (d) Unless the holder of a station license requests a change in call sign, the same call sign will be assigned to the station upon renewal or modification of a station license. (e) A reciprocal permit for alien amateur licensee cannot be renewed. A new reciprocal permit for alien amateur licensee may be issued upon proper application.

S 97.23 Mailing Address (a) Each application for a license and each application for a reciprocal permit for alien amateur licensee must show a mailing address in an area where the amateur service is regulated by the FCC and where the licensee or permittee can receive mail delivery by the United States Postal Service. Each application for a reciprocal permit for alien amateur licensee must also show the permittee's mailing address in the country of citizenship. (b) When there is a change in the mailing address for a person who has been granted an amateur operator/primary station license, the person must file a timely application Ham Radio In Plain English

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for a modification of the license. Revocation of the station license or suspension of the operator license may result when correspondence from the FCC is returned as undeliverable because the person failed to provide the correct mailing address. (c) When a person who has been granted a reciprocal permit for alien amateur licensee changes the mailing address where he or she can receive mail delivery by the United States Postal Service, the person must file an application for a new permit. Cancellation of the reciprocal permit for alien amateur licensee may result when correspondence from the FCC is returned as undeliverable because the permittee failed to provide the correct mailing address.

S 97.25 License Term (a) An amateur service license is normally granted for a 10-year term. (b) A reciprocal permit for alien amateur licensee is normally granted for a 1-year term.

S 97.27 FCC Modification of Station License (a) The FCC may modify a station license, either for a limited time or for the duration of the term thereof, if it determines: (1) That such action will promote the public interest, convenience, and necessity; or (2) That such action will promote fuller compliance with the provisions of the Communications Act of 1934, as amended, or of any treaty ratified by the United States. (b) When the FCC makes such a determination, it will issue an order of modification. The order will not become final until the licensee is notified in writing of the proposed action and the grounds and reasons therefore. The licensee will be given reasonable opportunity of no less than 30 days to protest the modification; except that, where safety of life or property is involved, a shorter period of notice may be provided. Any protest by a licensee of an FCC order of modification will be handled in accordance with the provisions of 47 U.S.C. S 316.


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S 97.29 Replacement License Document Each person who has been granted an amateur station license or reciprocal permit for alien amateur licensee whose original license document or permit document is lost, mutilated or destroyed must request a replacement. A statement of how the document was lost, mutilated, or destroyed must be attached to the request. A replacement document must bear the same expiration date as the document that it replaces.

Subpart B--Station Operation Standards S 97.101 General Standards (a) In all respects not specifically covered by FCC Rules, each amateur station must be operated in accordance with good engineering and good amateur practice. (b) Each station licensee and each control operator must cooperate in selecting transmitting channels and in making the most effective use of the amateur service frequencies. No frequency will be assigned for the exclusive use of any station. (c) At all times and on all frequencies, each control operator must give priority to stations providing emergency communications, except to stations transmitting communications for training drills and tests in RACES. (d) No amateur operator shall willfully or maliciously interfere with or cause interference to any radio communication or signal.

S 97.103 Station Licensee Responsibilities (a) The station licensee is responsible for the proper operation of the station in accordance with the FCC Rules. When the control operator is a different amateur operator than the station licensee, both persons are equally responsible for proper operation of the station. (b) The station licensee must designate the station control operator. The FCC will presume that the station licensee is also the control operator, unless documentation to the contrary is in the station records. Ham Radio In Plain English

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(c) The station licensee must make the station and the station records available for inspection upon request by an FCC representative. When deemed necessary by an EIC to assure compliance with FCC Rules, the station licensee must maintain a record of station operations containing such items of information as the EIC may require in accord with S 0.314(x) of the FCC Rules.

“I have not failed. I have just found 10,000 ways that won’t work.” ~ Thomas Edison, inventor

S 97.105 Control Operator Duties (a) The control operator must ensure the immediate proper operation of the station, regardless of the type of control. (b) A station may only be operated in the manner and to the extent permitted by the privileges authorized for the class of operator license held by the control operator.

S 97.107 Alien Control Operator Privileges (a) The privileges available to a control operator holding an amateur service license issued by the Government of Canada are: (1) The terms of the convention between the United States and Canada (TIAS no. 2508) relating to the operation by citizens of either country of certain radio equipment or stations in the other country; (2) The operating terms and conditions of the amateur service license issued by the Government of Canada; and (3) The applicable provisions of the FCC Rules, but not to exceed the control operator privileges of an FCC-issued Amateur Extra Class operator license. (b) The privileges available to a control operator holding an FCC-issued reciprocal permit for alien amateur licensee are:


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(1) The terms of the agreement between the alien's government and the United States; (2) The operating terms and conditions of the amateur service license issued by the alien's government; (3) The applicable provisions of the FCC Rules, but not to exceed the control operator privileges of an FCC-issued Amateur Extra Class operator license; and (4) None, if the holder of the reciprocal permit has obtained an FCC-issued operator/ primary station license. (c) At any time the FCC may, in its discretion, modify, suspend, or cancel the amateur service privileges within or over any area where radio services are regulated by the FCC of any Canadian amateur service licensee or alien reciprocal permittee.

S 97.109 Station Control (a) Each amateur station must have at least one control point. (b) When a station is being locally controlled, the control operator must be at the control point. Any station may be locally controlled. (c) When a station is being remotely controlled, the control operator must be at the control point. Any station may be remotely controlled. (d) When a station is being automatically controlled, the control operator need not be at the control point. Only stations transmitting RTTY or data emissions on the 6 m or shorter wavelength bands, and stations specifically designated elsewhere in this Part may be automatically controlled. Automatic control must cease upon notification by an EIC that the station is transmitting improperly or causing harmful interference to other stations. Automatic control must not be resumed without prior approval of the EIC. (e) No station may be automatically controlled while transmitting third- party communications, except a station participating as a forwarding station in a message forwarding system. Ham Radio In Plain English

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S 97.111 Authorized Transmissions (a) An amateur station may transmit the following types of two-way communications: (1) Transmissions necessary to exchange messages with other stations in the amateur service, except those in any country whose administration has given notice that it objects to such communications. The FCC will issue public notices of current arrangements for international communications; (2) Transmissions necessary to exchange messages with a station in another FCCregulated service while providing emergency communications; (3) Transmissions necessary to exchange messages with a United States government station, necessary to providing communications in RACES; and (4) Transmissions necessary to exchange messages with a station in a service not regulated by the FCC, but authorized by the FCC to communicate with amateur stations. An amateur station may exchange messages with a participating United States military station during an Armed Forces Day Communications Test. (b) In addition to one-way transmissions specifically authorized elsewhere in this Part, an amateur station may transmit the following types of one-way communications: (1) Brief transmissions necessary to make adjustments to the station; (2) Brief transmissions necessary to establishing two-way communications with other stations; (3) Telecommand; (4) Transmissions necessary to providing emergency communications; (5) Transmissions necessary to assisting persons learning, or improving proficiency in, the international Morse code; (6) Transmissions necessary to disseminate information bulletins; (7) Transmissions of telemetry.


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S 97.113 Prohibited Transmissions (a) No amateur station shall transmit: (1) Communications specifically prohibited elsewhere in this Part; (2) Communications for hire or for material compensation, direct or indirect, paid or promised, except as otherwise provided in these rules; (3) Communications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer. Amateur operators may, however, notify other amateur operators of the availability for sale or trade of apparatus normally used in an amateur station, provided that such activity is not conducted on a regular basis; (4) Music using a phone emission except as specifically provided elsewhere in this Section; communications intended to facilitate a criminal act; messages in codes or ciphers intended to obscure the meaning thereof, except as otherwise provided herein; obscene or indecent words or language; or false or deceptive messages, signals or identification; (5) Communications, on a regular basis, which could reasonably be furnished alternatively through other radio services. (b) An amateur station shall not engage in any form of broadcasting, nor may an amateur station transmit one-way communications except as specifically provided in these rules; nor shall an amateur station engage in any activity related to program production or news gathering for broadcasting purposes, except that communications directly related to the immediate safety of human life or the protection of property may be provided by amateur stations to broadcasters for dissemination to the public where no other means of communication is reasonably available before or at the time of the event. (c) A control operator may accept compensation as an incident of a teaching position during periods of time when an amateur station is used by that teacher as a part of classroom instruction at an educational institution.


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(d) The control operator of a club station may accept compensation for the periods of time when the station is transmitting telegraphy practice or information bulletins, provided that the station transmits such telegraphy practice and bulletins for at least 40 hours per week; schedules operations on at least six amateur service MF and HF bands using reasonable measures to maximize coverage; where the schedule of normal operating times and frequencies is published at least 30 days in advance of the actual transmissions; and where the control operator does not accept any direct or indirect compensation for any other service as a control operator. (e) No station shall retransmit programs or signals emanating from any type of radio station other than an amateur station, except propagation and weather forecast information intended for use by the general public and originated from United States Government stations and communications, including incidental music, originating on United States Government frequencies between a space shuttle and its associated Earth stations. Prior approval for shuttle retransmissions must be obtained from the National Aeronautics and Space Administration. Such retransmissions must be for the exclusive use of amateur operators. Propagation, weather forecasts, and shuttle retransmissions may not be conducted on a regular basis, but only occasionally, as an incident of normal amateur radio communications. (f) No amateur station, except an auxiliary, repeater or space station, may automatically retransmit the radio signals of other amateur stations.

“We didn’t lose the game. We just ran out of time.” ~ Vince Lombardi, coach

S 97.115 Third Party Communications (a) An amateur station may transmit messages for a third party to: (1) Any station within the jurisdiction of the United States. (2) Any station within the jurisdiction of any foreign government whose administration has made arrangements with the United States to allow amateur stations to be used Ham Radio In Plain English

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for transmitting international communications on behalf of third parties. No station shall transmit messages for a third party to any station within the jurisdiction of any foreign government whose administration has not made such an arrangement. This prohibition does not apply to a message for any third party who is eligible to be a control operator of the station. (b) The third party may participate in stating the message where: (1) The control operator is present at the control point and is continuously monitoring and supervising the third party's participation; and (2) The third party is not a prior amateur service licensee whose license was revoked; suspended for less than the balance of the license term and the suspension is still in effect; suspended for the balance of the license term and relicensing has not taken place; or surrendered for cancellation following notice of revocation, suspension or monetary forfeiture proceedings. The third party may not be the subject of a cease and desist order which relates to amateur service operation and which is still in effect. (c) At the end of an exchange of international third party communications, the station must also transmit in the station identification procedure the call sign of the station with which a third party message was exchanged.

S 97.117 International Communications Transmissions to a different country, where permitted, shall be made in plain language and shall be limited to messages of a technical nature relating to tests, and, to remarks of a personal character for which, by reason of their unimportance, recourse to the public telecommunications service is not justified.


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S 97.119 Station Identification (a) Each amateur station, except a space station or telecommand station, must transmit its assigned call sign on its transmitting channel at the end of each communication, and at least every 10 minutes during a communication, for the purpose of clearly making the source of the transmissions from the station known to those receiving the transmissions. No station may transmit unidentified communications or signals, or transmit as the station call sign, any call sign not authorized to the station. (b) The call sign must be transmitted with an emission authorized for the transmitting channel in one of the following ways: (1) By a CW emission. When keyed by an automatic device used only for identification, the speed must not exceed 20 words per minute; (2) By a phone emission in the English language. Use of a standard phonetic alphabet as an aid for correct station identification is encouraged; (3) By RTTY emission using a specified digital code when all or part of the communications is transmitted by RTTY or data emission; (4) By an image emission conforming to the applicable transmission standards, either color or monochrome, of S 73.682(a) of the FCC Rules when all or part of the communications are transmitted in the same image emission; or (5) By a CW or phone emission during SS emission transmission on a narrow bandwidth frequency segment. Alternatively, by the changing of one or more parameters of the emission so that a conventional CW or phone emission receiver can be used to determine the station call sign. (c) An indicator may be included with the call sign. It must be separated from the call sign by the slant mark or by any suitable word that denotes the slant mark. If the indicator is self-assigned it must be included after the call sign and must not conflict with any other indicator specified by the FCC rules or with any prefix assigned to another country.


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(d) When the operator license class held by the control operator exceeds that of the station licensee, an indicator consisting of the call sign assigned to the control operator's station must be included after the call sign. (e) When the control operator who is exercising the rights and privileges authorized by S 97.9(b) of this part, an indicator must be included after the call sign as follows: (1) For a control operator who has requested a license modification from Novice to Technician Class: KT; (2) For a control operator who has requested a license modification from Novice or Technician Class to General Class: AG; (3) For a control operator who has requested a license modification from Novice, Technician, or General Class operator to Advanced Class: AA; or (4) For a control operator who has requested a license modification from Novice, Technician, General, or Advanced Class operator to Amateur Extra Class: AE. (f) When the station is transmitting under the authority of a reciprocal permit for alien amateur licensee, an indicator consisting of the appropriate letter-numeral designating the station location must be included before the call sign issued to the station by the licensing country. When the station is transmitting under the authority of an amateur service license issued by the Government of Canada, a station location indicator must be included after the call sign. At least once during each intercommunication, the identification announcement must include the geographical location as nearly as possible by city and state, commonwealth or possession.

S 97.121 Restricted Operation (a) If the operation of an amateur station causes general interference to the reception of transmissions from stations operating in the domestic broadcast service when receivers of good engineering design, including adequate selectivity characteristics, are used to receive such transmissions, and this fact is made known to the amateur station licensee, the amateur station shall not be operated during the hours from 8 PM to Ham Radio In Plain English

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10:30 PM local time, and on Sunday for the additional period from 10:30 AM until 1 PM local time, upon the frequency or frequencies used when the interference is created. (b) In general, such steps as may be necessary to minimize interference to stations operating in other services may be required after investigation by the FCC.

Subpart C--Special Operations S 97.201 Auxiliary Station (a) Any amateur station licensed to a holder of a Technician, General, Advanced or Amateur Extra Class operator license may be an auxiliary station. A holder of a Technician, General, Advanced or Amateur Extra Class operator license may be the control operator of an auxiliary station, subject to the privileges of the class of operator license held. (b) An auxiliary station may transmit only on the 1.25 m and shorter wavelength frequency bands, except the 222.00-222.15 MHz, 431-433 MHz and 435-438 MHz segments. (c) Where an auxiliary station causes harmful interference to another auxiliary station, the licensees are equally and fully responsible for resolving the interference unless one station's operation is recommended by a frequency coordinator and the other station's is not. In that case, the licensee of the non-coordinated auxiliary station has primary responsibility to resolve the interference. (d) An auxiliary station may be automatically controlled. (e) An auxiliary station may transmit one-way communications.

“The object of war is not to die for your country but to make the other bastard die for his.” ~ General, George Patton, army general


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S 97.203 Beacon Station (a) Any amateur station licensed to a holder of a Technician, General, Advanced or Amateur Extra Class operator license may be a beacon. A holder of a Technician, General, Advanced or Amateur Extra Class operator license may be the control operator of a beacon, subject to the privileges of the class of operator license held. (b) A beacon must not concurrently transmit on more than one channel in the same amateur service frequency band, from the same station location. (c) The transmitter power of a beacon must not exceed 100 W. (d) A beacon may be automatically controlled while it is transmitting on the 28.20-28.30 MHz, 50.06-50.08 MHz, 144.275-144.300 MHz, 222.05-222.06 MHz, or 432.300-432.400 MHz segments, or on the 33 cm and shorter wavelength bands. (e) Before establishing an automatically controlled beacon in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944. (1) The notification must include the geographical coordinates of the antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power. (2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate. (f) A beacon must cease transmissions upon notification by an EIC that the station is operating improperly or causing undue interference to other operations. The beacon may not resume transmitting without prior approval of the EIC. (g) A beacon may transmit one-way communications. Ham Radio In Plain English

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S 97.205 Repeater Station (a) Any amateur station licensed to a holder of a Technician, General, Advanced or Amateur Extra Class operator license may be a repeater. A holder of a Technician, General, Advanced or Amateur Extra Class operator license may be the control operator of a repeater, subject to the privileges of the class of operator license held. (b) A repeater may receive and retransmit only on the 10 m and shorter wavelength frequency bands except the 28.0-29.5 MHz, 50.0-51.0 MHz, 144.0- 144.5 MHz, 145.5-146.0 MHz, 222.00-222.15 MHz, 431.0-433.0 MHz and 435.0- 438.0 MHz segments. (c) Where the transmissions of a repeater cause harmful interference to another repeater, the two station licensees are equally and fully responsible for resolving the interference unless the operation of one station is recommended by a frequency coordinator and the operation of the other station is not. In that case, the licensee of the noncoordinated repeater has primary responsibility to resolve the interference. (d) A repeater may be automatically controlled. (e) Ancillary functions of a repeater that are available to users on the input channel are not considered remotely controlled functions of the station. Limiting the use of a repeater to only certain user stations is permissible. (f) Before establishing a repeater in the National Radio Quiet Zone or before changing the transmitting frequency, transmitter power, antenna height or directivity, or the location of an existing repeater, the station licensee must give written notification thereof to the Interference Office, National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944. (1) The notification must include the geographical coordinates of the station antenna, antenna ground elevation above mean sea level (AMSL), antenna center of radiation above ground level (AGL), antenna directivity, proposed frequency, type of emission, and transmitter power.


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(2) If an objection to the proposed operation is received by the FCC from the National Radio Astronomy Observatory at Green Bank, Pocahontas County, WV, for itself or on behalf of the Naval Research Laboratory at Sugar Grove, Pendleton County, WV, within 20 days from the date of notification, the FCC will consider all aspects of the problem and take whatever action is deemed appropriate. (g) The control operator of a repeater that retransmits inadvertently communications that violate the rules in this Part is not accountable for the communications in violation.

S 97.207 Space Station (a) Any amateur station may be a space station. A holder of any class operator license may be the control operator of a space station, subject to the privileges of the class of operator license held by the control operator. (b) A space station must be capable of affecting a cessation of transmissions by telecommand whenever such cessation is ordered by the FCC. (c) The following frequency bands and segments are authorized to space stations: (1) The 17 m, 15 m, 12 m and 10 m bands, 6 mm, 4 mm, 2 mm and 1 mm bands; and (2) The 7.0-7.1 MHz, 14.00-14.25 MHz, 144-146 MHz, 435-438 MHz, 1260- 1270 MHz and 2400-2450 MHz, 3.40-3.41 GHz, 5.83-5.85 GHz, 10.45-10.50 GHz and 24.00-24.05 GHz segments. (d) A space station may automatically retransmit the radio signals of Earth stations and other space stations. (e) A space station may transmit one-way communications. (f) Space telemetry transmissions may consist of specially coded messages intended to facilitate communications or related to the function of the spacecraft. (g) The licensee of each space station must give two written, pre-space station notifications to the Private Radio Bureau, FCC, Washington, DC 20554. Each notification must be in accord with the provisions of Articles 11 and 13 of the Radio Regulations.


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(1) The first notification is required no less than 27 months prior to initiating space station transmissions and must specify the information required by Appendix 4, and Resolution No. 642 of the Radio Regulations. (2) The second notification is required no less than five months prior to initiating space station transmissions and must specify the information required by Appendix 3 and Resolution No. 642 of the Radio Regulations. (h) The licensee of each space station must give a written, in-space station notification to the Private Radio Bureau, FCC, Washington, DC 20554, no later than seven days following initiation of space station transmissions. The notification must update the information contained in the pre-space notification. (i) The licensee of each space station must give a written, post-space station notification to the Private Radio Bureau, FCC, Washington, DC 20554, no later than three months after termination of the space station transmissions. When the termination is ordered by the FCC, notification is required no later than 24 hours after termination.

“You can get more with a kind word and a gun than you can with a kind word alone.” ~ Al Capone, gangster S 97.209 Earth Station (a) Any amateur station may be an Earth station. A holder of any class operator license may be the control operator of an Earth station, subject to the privileges of the class of operator license held by the control operator. (b) The following frequency bands and segments are authorized to Earth stations: (1) The 17 m, 15 m, 12 m and 10 m bands, 6 mm, 4 mm, 2 mm and 1 mm bands; and (2) The 7.0-7.1 MHz, 14.00-14.25 MHz, 144-146 MHz, 435-438 MHz, 1260- 1270 MHz and 2400-2450 MHz, 3.40-3.41 GHz, 5.65-5.67 GHz, 10.45-10.50 GHz and 24.00-24.05 GHz segments.


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S 97.211 Space Telecommand Station (a) Any amateur station designated by the licensee of a space station is eligible to transmit as a telecommand station for that space station, subject to the privileges of the class of operator license held by the control operator. (b) A telecommand station may transmit special codes intended to obscure the meaning of telecommand messages to the station in space operation. (c) The following frequency bands and segments are authorized to telecommand stations: (1) The 17 m, 15 m, 12 m and 10 m bands, 6 mm, 4 mm, 2 mm and 1 mm bands; and (2) The 7.0-7.1 MHz, 14.00-14.25 MHz, 144-146 MHz, 435-438 MHz, 1260- 1270 MHz and 2400-2450 MHz, 3.40-3.41 GHz, 5.65-5.67 GHz, 10.45-10.50 GHz and 24.00-24.05 GHz segments. (d) A telecommand station may transmit one-way communications.

S 97.213 Telecommand of an Amateur Station An amateur station on or within 50 km of the Earth's surface may be under telecommand where: (a) There is a radio or wireline control link between the control point and the station sufficient for the control operator to perform his/her duties. If radio, the control link must use an auxiliary station. A control link using a fiber optic cable or another telecommunication service is considered wireline. (b) Provisions are incorporated to limit transmission by the station to a period of no more than three minutes in the event of malfunction in the control link. (c) The station is protected against making, willfully or negligently, unauthorized transmissions.


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(d) A photocopy of the station license and a label with the name, address, and telephone number of the station licensee and at least one designated control operator is posted in a conspicuous place at the station location.

S 97.215 Telecommand of Model Craft An amateur station transmitting signals to control a model craft may be operated as follows: (a) The station identification procedure is not required for transmissions directed only to the model craft, provided that a label indicating the station call sign and the station licensee's name and address is affixed to the station transmitter. (b) The control signals are not considered codes or ciphers intended to obscure the meaning of the communication. (c) The transmitter power must not exceed 1 W.

S 97.217 Telemetry Telemetry transmitted by an amateur station on or within 50 km of the Earth's surface is not considered to be codes or ciphers intended to obscure the meaning of communications. S 97.219 Message Forwarding System (a) Any amateur station may participate in a message forwarding system, subject to the privileges of the class of operator license held. (b) For stations participating in a message forwarding system, the control operator of the station originating a message is primarily accountable for any violation of the rules in this Part contained in the message. (c) Except as noted in paragraph (d) of this section, for stations participating in a message forwarding system, the control operators of forwarding stations that retransmit Ham Radio In Plain English

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inadvertently communications that violate the rules in this Part are not accountable for the violative communications. They are, however, responsible for discontinuing such communications once they become aware of their presence. (d) For stations participating in a message forwarding system, the control operator of the first forwarding station must: (1) Authenticate the identity of the station from which it accepts communication on behalf of the system; or (2) Accept accountability for any violation of the rules in this Part contained in messages it retransmits to the system.

Subpart D--Technical Standards

97.303 Frequency Sharing Requirements The following is a summary of the frequency sharing requirements that apply to amateur station transmissions on the frequency bands specified in S 97.301 of this Part. (For each ITU Region, each frequency band allocated to the amateur service is designated as either a secondary service or a primary service. A station in a secondary service must not cause harmful interference to, and must accept interference from, stations in a primary service. See SS 2.105 and 2.106 of the FCC Rules, United States Table of Frequency Allocations for complete requirements.) (a) Where, in adjacent ITU Regions or Subregions, a band of frequencies is allocated to different services of the same category, the basic principle is the equality of right to operate. The stations of each service in one region must operate so as not to cause harmful interference to services in the other Regions or Subregions. (See ITU Radio Regulations, No. 346 (Geneva, 1979).) (b) No amateur station transmitting in the 1900-2000 kHz segment, the 70 cm band, the 33 cm band, the 13 cm band, the 9 cm band, the 5 cm band, the 3 cm band, the 24.05-24.25 GHz segment, the 76-81 GHz segment, the 144-149 GHz segment and


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the 241-248 GHz segment shall cause harmful interference to, nor is protected from interference due to the operation of, the Government radio location service. (c) No amateur station transmitting in the 1900-2000 kHz segment, the 3 cm band, the 76-81 GHz segment, the 144-149 GHz segment and the 241-248 GHz segment shall cause harmful interference to, nor is protected from interference due to the operation of, stations in the non-Government radiolocation service. (d) No amateur station transmitting in the 30 meter band shall cause harmful interference to stations authorized by other nations in the fixed service. The licensee of the amateur station must make all necessary adjustments, including termination of transmissions, if harmful interference is caused. (e) Reserved (f) In the 70 cm band: (1) No amateur station shall transmit from north of Line A in the 420- 430 MHz segment. (2) The 420-430 MHz segment is allocated to the amateur service in the United States on a secondary basis, and is allocated in the fixed and mobile (except aeronautical mobile) services in the International Table of allocations on a primary basis. No amateur station transmitting in this band shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the fixed and mobile (except aeronautical mobile) services. (3) The 430-440 MHz segment is allocated to the amateur service on a secondary basis in ITU Regions 2 and 3. No amateur station transmitting in this band in ITU Regions 2 and 3 shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the radiolocation service. In ITU Region 1, the 430-440 MHz segment is allocated to the amateur service on a co-primary basis with the radio-location service. As between these two services in this band in ITU Region 1, the basic principle that applies is the equality of right to operate. Amateur stations authorized by the United States and radiolocation stations


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authorized by other nations in ITU Region 1 shall operate so as not to cause harmful interference to each other. (4) No amateur station transmitting in the 449.75-450.25 MHz segment shall cause interference to, nor is protected from interference due to the operation of stations in, the space operation service and the space research service or Government or nonGovernment stations for space telecommand. (g) In the 33 cm band: (1) No amateur station shall transmit from within the States of Colorado and Wyoming, bounded on the south by latitude 39 N, on the north by latitude 42 N, on the east by longitude 105 W, and on the west by longitude 180 W.1 This band is allocated on a secondary basis to the amateur service subject to not causing harmful interference to, and not receiving protection from any interference due to the operation of, industrial, scientific and medical devices, automatic vehicle monitoring systems or Government stations authorized in this band. (2) No amateur station shall transmit from those portions of the States of Texas and New Mexico bounded on the south by latitude 31 41' N, on the north by latitude 34 30' N, on the east by longitude 104 11' W, and on the west by longitude 107 30' W. (h) No amateur station transmitting in the 23 cm band, the 3 cm band, the 24.05-24.25 GHz segment, the 76-81 GHz segment, the 144-149 GHz segment and the 241-248 GHz segment shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the radiolocation service. (i) In the 1240-1260 MHz segment, no amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations in the radio navigation-satellite service, the aeronautical radio navigation service, or the radiolocation service. (j) In the 13 cm band: (1) The amateur service is allocated on a secondary basis in all ITU Regions. In ITU Region 1, no amateur station shall cause harmful interference to, and is not protected Ham Radio In Plain English

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from interference due to the operation of, stations authorized by other nations in the fixed service. In ITU Regions 2 and 3, no station shall cause harmful interference to, and is not protected from interference due to the operation of, stations authorized by other nations in the fixed, mobile and radiolocation services. (2) In the United States, the 2300-2310 MHz segment is allocated to the amateur service on a co-secondary basis with the Government fixed and mobile services. In this segment, the fixed and mobile services must not cause harmful interference to the amateur service. No amateur station transmitting in the 2400-2450 MHz segment is protected from interference due to the operation of industrial, scientific and medical devices on 2450 MHz. (k) No amateur station transmitting in the 3.332-3.339 GHz and 3.3458- 3525 GHz segments, the 2.5 mm band, the 144.68-144.98 GHz, 145.45-145.75 GHz and 146.82-147.12 GHz segments and the 343-348 GHz segment shall cause harmful interference to stations in the radio astronomy service. No amateur station transmitting in the 300-302 GHz, 324-326 GHz, 345-347 GHz, 363-365 GHz and 379-381 GHz segments shall cause harmful interference to stations in the space research service (passive) or Earth exploration-satellite service (passive). (l) In the 9 cm band: (1) In ITU Regions 2 and 3, the band is allocated to the amateur service on a secondary basis. (2) In the United States, the band is allocated to the amateur service on a cosecondary basis with the non-Government radiolocation service. (3) In the 3.3-3.4 GHz segment, no amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the fixed and fixed-satellite service. (4) In the 3.4-3.5 GHz segment, no amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the fixed and fixed-satellite service. (m) In the 5 cm band: Ham Radio In Plain English

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(1) In the 5.650-5.725 GHz segment, the amateur service is allocated in all ITU Regions on a co-secondary basis with the space research (deep space) service. (2) In the 5.725-5.850 GHz segment, the amateur service is allocated in all ITU Regions on a secondary basis. No amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the fixed-satellite service in ITU Region 1. (3) No amateur station transmitting in the 5.725-5.875 GHz segment is protected from interference due to the operation of industrial, scientific and medical devices operating on 5.8 GHz. (4) In the 5.650-5.850 GHz segment, no amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the radiolocation service. (5) In the 5.850-5.925 GHz segment, the amateur service is allocated in ITU Region 2 on a co-secondary basis with the radiolocation service. In the United States, the segment is allocated to the amateur service on a secondary basis to the non-Government fixed-satellite service. No amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the fixed, fixed-satellite and mobile services. No amateur station shall cause harmful interference to, nor is protected from interference due to the operation of, stations in the non-Government fixed-satellite service. (n) In the 3 cm band: (1) In the United States, the 3 cm band is allocated to the amateur service on a cosecondary basis with the non-government radiolocation service. (2) In the 10.00-10.45 GHz segment in ITU Regions 1 and 3, no amateur station shall cause interference to, nor is protected from interference due to the operation of, stations authorized by other nations in the fixed and mobile services. (o) No amateur station transmitting in the 1.2 cm band is protected from interference due to the operation of industrial, scientific and medical devices on 24.125 GHz. In the United States, the 24.05-24.25 GHz segment is allocated to the amateur service on a Ham Radio In Plain English

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co-secondary basis with the nongovernment radiolocation and Government and nongovernment Earth exploration-satellite (active) services. (p) The 2.5 mm band is allocated to the amateur service on a secondary basis. No amateur station transmitting in this band shall cause harmful interference to, nor is protected from interference due to the operation of, stations in the fixed, inter-satellite and mobile services. (q) No amateur station transmitting in the 244-246 GHz segment of the 1 mm band is protected from interference due to the operation of industrial, scientific and medical devices on 245 GHz.

“It is now possible for a flight attendant to get a pilot pregnant.” ~ Richard Ferris, president of United Airlines

S 97.307 Emission Standards (a) No amateur station transmission shall occupy more bandwidth than necessary for the information rate and emission type being transmitted, in accordance with good amateur practice. (b) Emissions resulting from modulation must be confined to the band or segment available to the control operator. Emissions outside the necessary bandwidth must not cause splatter or key click interference to operations on adjacent frequencies. (c) All spurious emissions from a station transmitter must be reduced to the greatest extent practicable. If any spurious emission, including chassis or power line radiation, causes harmful interference to the reception of another radio station, the licensee of the interfering amateur station is required to take steps to eliminate the interference, in accordance with good engineering practice. (d) The mean power of any spurious emission from a station transmitter or external RF power amplifier transmitting on a frequency below 30 MHz must not exceed 50 mW and must be at least 40 dB below the mean power of the fundamental emission. For a Ham Radio In Plain English

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transmitter of mean power less than 5 W, the attenuation must be at least 30 dB. A transmitter built before April 15, 1977, or first marketed before January 1, 1978, is exempt from this requirement. (e) The mean power of any spurious emission from a station transmitter or external RF power amplifier transmitting on a frequency between 30-225 MHz must be at least 60 dB below the mean power of the fundamental. For a transmitter having a mean power of 25 W or less, the mean power of any spurious emission supplied to the antenna transmission line must not exceed 25 uW and must be at least 40 dB below the mean power of the fundamental emission, but need not be reduced below the power of 10 uW. A transmitter built before April 15, 1977, or first marketed before January 1, 1978, is exempt from this requirement. (f) The following standards and limitations apply to transmissions on the frequencies specified in S 97.305(c) of this Part. (1) No angle-modulated emission may have a modulation index greater than 1 at the highest modulation frequency. (2) No non-phone emission shall exceed the bandwidth of a communications quality phone emission of the same modulation type. The total bandwidth of an independent sideband emission (having B as the first symbol), or a multiplexed image and phone emission, shall not exceed that of a communications quality A3E emission. (3) Only a RTTY or data emission using a specified digital code listed in S 97.309(a) of this Part may be transmitted. The symbol rate must not exceed 300 bauds, or for frequency-shift keying, the frequency shift between mark and space must not exceed 1 kHz. (4) Only a RTTY or data emission using a specified digital code listed in S 97.309(a) of this Part may be transmitted. The symbol rate must not exceed 1200 bauds. For frequency-shift keying, the frequency shift between mark and space must not exceed 1 kHz. (5) A RTTY, data or multiplexed emission using a specified digital code listed in S 97.309(a) of this Part may be transmitted. The symbol rate must not exceed 19.6 kiloHam Radio In Plain English

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bauds. A RTTY, data or multiplexed emission using an unspecified digital code under the limitations listed in S 97.309(b) of this Part also may be transmitted. The authorized bandwidth is 20 kHz. (6) A RTTY, data or multiplexed emission using a specified digital code listed in S 97.309(a) of this Part may be transmitted. The symbol rate must not exceed 56 kilobauds. A RTTY, data or multiplexed emission using an unspecified digital code under the limitations listed in S 97.309(b) of this Part also may be transmitted. The authorized bandwidth is 100 kHz. (7) A RTTY, data or multiplexed emission using a specified digital code listed in S 97.309(a) of this Part or an unspecified digital code under the limitations listed in S 97.309(b) of this Part may be transmitted. (8) A RTTY or data emission having designators with A, B, C, D, E, F, G, H, J or R as the first symbol; 1, 2, 7 or 9 as the second symbol; and D or W as the third symbol is also authorized. (9) A station having a control operator holding a Novice or Technician Class operator license may only transmit a CW emission using the international Morse code. (10) A station having a control operator holding a Novice or Technician Class operator license may only transmit a CW emission using the international Morse code or phone emissions J3E and R3E. (11) Phone and image emissions may be transmitted only by stations located in ITU Regions 1 and 3, and by stations located within ITU Region 2 that are west of 130 West longitude or south of 20 North latitude. (12) Emission F8E may be transmitted.


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S 97.309 RTTY and Data Emission Codes (a) Where authorized by S 97.305(c) and 97.307(f) of this Part, an amateur station may transmit a RTTY or data emission using the following specified digital codes: (1) The 5-unit, start-stop, International Telegraph Alphabet No. 2, code defined in International Telegraph and Telephone Consultative Committee Recommendation F.1, Division C (commonly known as Baudot). (2) The 7-unit code, specified in International Radio Consultative Committee Recommendation CCIR 476-2 (1978), 476-3 (1982), 476-4 (1986) or 625 (1986) (commonly known as AMTOR). (3) The 7-unit code defined in American National Standards Institute X3.4-1977 or International Alphabet No. 5 defined in International Telegraph and Telephone Consultative Committee Recommendation T.50 or in International Organization for Standardization, International Standard ISO 646 (1983), and extensions as provided for in CCITT Recommendation T.61 (Malaga-Torremolinos, 1984) (commonly known as ASCII). (b) Where authorized by S S 97.305(c) and 97.307(f) of this Part, a station may transmit a RTTY or data emission using an unspecified digital code, except to a station in a country with which the United States does not have an agreement permitting the code to be used. RTTY and data emissions using unspecified digital codes must not be transmitted for the purpose of obscuring the meaning of any communication. When deemed necessary by an EIC to assure compliance with the FCC Rules, a station must: (1) Cease the transmission using the unspecified digital code; (2) Restrict transmissions of any digital code to the extent instructed; (3) Maintain a record, convertible to the original information, of all digital communications transmitted. “I went to a restaurant that serves breakfast ‘at any time.’ So I ordered French toast during the Renaissance.” ~ Steven Wright, comedian


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S 97.311 SS Emission Types (a) SS emission transmissions by an amateur station are authorized only for communications between points within areas where the amateur service is regulated by the FCC. SS emission transmissions must not be used for the purpose of obscuring the meaning of any communication. (b) Stations transmitting SS emission must not cause harmful interference to stations employing other authorized emissions, and must accept all interference caused by stations employing other authorized emissions. For the purposes of this paragraph, unintended triggering of carrier operated repeaters is not considered to be harmful interference. (c) Only the following types of SS emission transmissions are authorized (hybrid SS emission transmissions involving both spreading techniques are prohibited): (1) Frequency hopping where the carrier of the transmitted signal is modulated with unciphered information and changes frequency at fixed intervals under the direction of a high speed code sequence. (2) Direct sequence where the information is modulo-2 added to a high speed code sequence. The combined information and code are then used to modulate the RF carrier. The high speed code sequence dominates the modulation function, and is the direct cause of the wide spreading of the transmitted signal. (d) The only spreading sequences that are authorized are from the output of one binary linear feedback shift register (which may be implemented in hardware or software). (1) Only the following sets of connections may be used: Number of stages

Taps used

in shift register

in feedback

7

7, 1.

13

13, 4, 3, and 1.

19

19, 5, 2, and 1.


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(2) The shift register must not be reset other than by its feedback during an individual transmission. The shift register output sequence must be used without alteration. (3) The output of the last stage of the binary linear feedback shift register must be used as follows: (i) For frequency hopping transmissions using x frequencies, n consecutive bits from the shift register must be used to select the next frequency from a list of frequencies sorted in ascending order. Each consecutive frequency must be selected by a consecutive block of n bits. (Where n is the smallest integer greater than log2X.) (ii) For direct sequence transmissions using m-ary modulation, consecutive blocks of log2 m bits from the shift register must be used to select the transmitted signal during each interval. (e) The station records must document all SS emission transmissions and must be retained for a period of one year following the last entry. The station records must include sufficient information to enable the FCC, using the information contained therein, to demodulate all transmissions. The station records must contain at least the following: (1) A technical description of the transmitted signal; (2) Pertinent parameters describing the transmitted signal including the frequency or frequencies of operation and, where applicable, the chip rate, the code rate, the spreading function, the transmission protocol(s) including the method of achieving synchronization, and the modulation type; (3) A general description of the type of information being conveyed (voice, text, memory dump, facsimile, television, etc.); (4) The method and, if applicable, the frequency or frequencies used for station identification; and (5) The date of beginning and the date of ending use of each type of transmitted signal.


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(f) When deemed necessary by an EIC to assure compliance with this Part, a station licensee must: (1) Cease SS emission transmissions; (2) Restrict SS emission transmissions to the extent instructed; and (3) Maintain a record, convertible to the original information (voice, text, image, etc.) of all spread spectrum communications transmitted. (g) The transmitter power must not exceed 100 W.

S 97.313 Transmitter Power Standards (a) An amateur station must use the minimum transmitter power necessary to carry out the desired communications. (b) No station may transmit with a transmitter power exceeding 1.5 kW PEP. (c) No station may transmit with a transmitter power exceeding 200 W PEP on: (1) The 3.675-3.725 MHz, 7.10-7.15 MHz, 10.10-10.15 MHz and 21.1-21.2 MHz segments; (2) The 28.1-28.5 MHz segment when the control operator is a Novice or Technician operator; or (3) The 7.050-7.075 MHz segment when the station is within ITU Regions 1 or 3. (d) No station may transmit with a transmitter power exceeding 25 W PEP on the VHF 1.25 m band when the control operator is a Novice operator. (e) No station may transmit with a transmitter power exceeding 5 W PEP on the UHF 23 cm band when the control operator is a Novice operator. (f) No station may transmit with a transmitter power exceeding 50 W PEP on the UHF 70 cm band from an area specified in footnote US7 to S 2.106 of the FCC Rules, unless expressly authorized by the FCC after mutual agreement, on a case-by-case basis, between the EIC of the applicable field facility and the military area frequency coordinator at the applicable military base. An Earth station or telecommand station,


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however, may transmit on the 435-438 MHz segment with a maximum of 611 W effective radiated power (1 kW equivalent isotropically radiated power) without the authorization otherwise required. The transmitting antenna elevation angle between the lower half-power (–3 dB relative to the peak or antenna bore sight) point and the horizon must always be greater than ten. (g) No station may transmit with a transmitter power exceeding 50 watts PEP on the 33 cm band from within 241 km of the boundaries of the White Sands Missile Range. Its boundaries are those portions of Texas and New Mexico bounded on the south by latitude 31 41' North, on the east by longitude 104 11' West, on the north by latitude 34 30' North, and on the west by longitude 107 30' West.

“We had gay burglars the other night. They broke in and rearranged the furniture.” ~ Robin Williams

S 97.315 Type Acceptance of External RF Power Amplifiers (a) No more than one unit of one model of an external RF power amplifier capable of operation below 144 MHz may be constructed or modified during any calendar year by an amateur operator for use at a station without a grant of type acceptance. No amplifier capable of operation below 144 MHz may be constructed or modified by a nonamateur operator without a grant of type acceptance from the FCC. (b) Any external RF power amplifier or external RF power amplifier kit (see S 2.815 of the FCC Rules), manufactured, imported or modified for use in a station or attached at any station must be type accepted for use in the amateur service in accordance with Subpart J of Part 2 of the FCC Rules. This requirement does not apply if one or more of the following conditions are met: (1) The amplifier is not capable of operation on frequencies below 144 MHz. For the purpose of this part, an amplifier will be deemed to be incapable of operation below 144 MHz if it is not capable of being easily modified to increase its amplification characteristics below 120 MHz and either: Ham Radio In Plain English

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(i) The mean output power of the amplifier decreases, as frequency decreases from 144 MHz, to a point where 0 dB or less gain is exhibited at 120 MHz; or (ii) The amplifier is not capable of amplifying signals below 120 MHz even for brief periods without sustaining permanent damage to its amplification circuitry. (2) The amplifier was manufactured before April 28, 1978, and has been issued a marketing waiver by the FCC, or the amplifier was purchased before April 28, 1978, by an amateur operator for use at that amateur operator's station. (3) The amplifier was: (i) Constructed by the licensee, not from an external RF power amplifier kit, for use at the licensee's station; or (ii) Modified by the licensee for use at the licensee's station. (4) The amplifier is sold by an amateur operator to another amateur operator or to a dealer. (5) The amplifier is purchased in used condition by an equipment dealer from an amateur operator and the amplifier is further sold to another amateur operator for use at that operator's station. (c) A list of type accepted equipment may be inspected at FCC headquarters in Washington, DC or at any FCC field location. Any external RF power amplifier appearing on this list as type accepted for use in the amateur service may be marketed for use in the amateur service.

S 97.317 Standards for Type Acceptance of External RF Power Amplifiers (a) To receive a grant of type acceptance, the amplifier must satisfy the spurious emission standards of S 97.307(d) or (e) of this Part, as applicable, when the amplifier is: (1) Operated at its full output power; (2) Placed in the "standby" or "off" positions, but still connected to the transmitter; and


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(3) Driven with at least 50 W mean RF input power (unless higher drive level is specified). (b) To receive a grant of type acceptance, the amplifier must not be capable of operation on any frequency or frequencies between 24 MHz and 35 MHz. The amplifier will be deemed incapable of such operation if it: (1) Exhibits no more than 6 dB gain between 24 MHz and 26 MHz and between 28 MHz and 35 MHz. (This gain will be determined by the ratio of the input RF driving signal (mean power measurement) to the mean RF output power of the amplifier); and (2) Exhibits no amplification (0 dB gain) between 26 MHz and 28 MHz. (c) Type acceptance may be denied when denial would prevent the use of these amplifiers in services other than the amateur service. The following features will result in dismissal or denial of an application for the type acceptance: (1) Any accessible wiring which, when altered, would permit operation of the amplifier in a manner contrary to the FCC rules; (2) Circuit boards or similar circuitry to facilitate the addition of components to change the amplifier's operating characteristics in a manner contrary to the FCC rules; (3) Instructions for operation or modification of the amplifier in a manner contrary to the FCC rules; (4) Any internal or external controls or adjustments to facilitate operation of the amplifier in a manner contrary to the FCC rules; (5) Any internal RF sensing circuitry or any external switch, the purpose of which is to place the amplifier in the transmit mode; (6) The incorporation of more gain in the amplifier than is necessary to operate in the amateur service; for purposes of this paragraph, the amplifier must: (i) Not be capable of achieving designed output power when driven with less than 40 W mean RF input power; (ii) Not be capable of amplifying the input RF driving signal by more than 15 dB, unless the amplifier has a designed transmitter power of less than 1.5 kW (in such a Ham Radio In Plain English

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case, gain must be reduced by the same number of dB as the transmitter power relationship to 1.5 kW; This gain limitation is determined by the ratio of the input RF driving signal to the RF output power of the amplifier where both signals are expressed in peak envelope power or mean power); (iii) Not exhibit more gain than permitted by paragraph (c)(6)(ii) of this Section when driven by an RF input signal of less than 50 W mean power; and (iv) Be capable of sustained operation at its designed power level. (7) Any attenuation in the input of the amplifier which, when removed or modified, would permit the amplifier to function at its designed transmitter power when driven by an RF frequency input signal of less than 50 W mean power; or (8) Any other features designed to facilitate operation in a telecommunication service other than the Amateur Radio Services, such as the Citizens Band (CB) Radio Service.


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Chapter 7 Amateur Radio Practice Safety "I'm always amazed to hear of air crash victims so badly mutilated that they have to be identified by their dental records. What I can't understand is if they don't know who you are, how do they know who your dentist is?" ~ Paul Merton, comedian

Lightning Damage It is always advisable to ground the antenna when not in use. If there is a possibility of a storm, all the station equipment can be turned off. The antenna’s cables can be disconnected and hooked to the ground.

Safety of the station Grounding All the station equipment should be grounded to prevent any electrical shock. What is a Ground? A ground is a low-impedance electrical connection to earth. All transmitting antenna systems need an excellent ground system to provide proper operator safety and optimum radiation of the maximum amount of RF energy into the air. There are three types of ground. Power Line Ground It is the ground found at the power box on home's electrical service connection. It provides overall electrical safety for the building and property. DC Ground (Safety Ground) This is a strap or wire placed from radio equipment to a convenient cold water pipe or ground rod to eliminate the hazard of electrical shock. In case of a mobile con-


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nection in an automobile, this wire is the one that connects the ground stud on the rear of the radio to the negative terminal of the battery, or the engine block.

RF Ground RF ground is a low-impedance path for RF to reach Earth. Normally, the DC Ground and the RF Ground are served by a common connection.

High Voltage Power Supplies High voltage power supply deals with very high voltages. The manufacturers of such equipment are bound to use interlock switches in the power supply. This facilitates the disconnection of AC power to the supply, while the cabinet is opened for repairs. This is done to avoid electrical shocks.

Antenna Safety When someone is on the antenna for repair activities, it is best to wear a helmet. Those on the ground should also wear a helmet. The antennas and feed-lines should always be clear of power lines.

Safety of the Equipment The U.S. occupational hazard standard for the people who work with amateur radio is 10 m Watts/square cm. Many studies have revealed that for 99 percent of the population, the total exposure is less than .001 m Watts per square cm. This is very low compared to the current U.S. standard. But the situation changes when close to an operating antenna. This will be much more than the standard value.


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Hazardous Voltages Since 30 volts is enough to kill a person, one must take the necessary precautions while working on high voltage. An electric current as feeble as 1/10th of an ampere can be fatal. The body part most affected by an electric shock is the heart. That is why shocks sometimes cause death. Standing Wave Ratio (SWR) The standing wave ratio provides the information on the mismatch between the antenna and the radio. A mismatch occurs when some of the power sent to the antenna returns to the radio. This ratio between the voltage sent to the antenna and the voltage reflected gives the SWR reading. If there is a mismatch, then the performance level of the radio will be affected. SWR Readings - How Are They Rated? 1:1 – This is the best ratio. (The best impedance match has been attained.) 1.5:1 – Excellent SWR match. 2:1-- A good SWR reading. 2.5:1 - An okay SWR reading. 3:1 - Poor SWR reading. 4:1 - Bad SWR reading. 5:1 - Very bad SWR reading. It is time to fix the antenna.

Fixing a Bad SWR Reading A very high SWR reading denotes an incorrect length. Another chance is that the connection along the feed line may be shorted somewhere. Otherwise, the length of the antenna needs to be changed. Lengthening If the SWR reading at the low end (frequency) of the band is 5:1 and at the higher end is 2 5, then the antenna needs to be lengthened. Ham Radio In Plain English

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Shortening If the SWR reading of the lower end is 2.5:1 and at the higher end is 5:1, then the length of the antenna must be shortened. “Some people see things that are and ask, Why? Some people dream of things that never were and ask, Why not? Some people have to go to work and don't have time for all that.” ~ George Carlin, comedian

Meters and Measurements

Voltmeter Voltmeter is a device used to measure the voltage of a portion of a circuit. While measuring, the voltmeters are connected “parallel” across the circuit.

Ammeter Ammeter is used to measure current in a circuit. Ammeter shows the current flowing in amperes through the circuit. The ammeter is placed in series with the circuit.

Multimeter A multimeter is multipurpose equipment, which can be used to measure the current voltage as well as resistance.

RF Wattmeter This device measures the quantity of radio frequency energy flowing out of the radio. It is measured in Watts; hence the name Wattmeter. It generally operates at 50 ohms line impedance.


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Directional Wattmeter This Wattmeter measures forward and reflected power. When a mismatch occurs, this can be used to detect the power going in the direction towards the antenna and the power going towards the radio. Peak Reading Wattmeter The peak energy emitted by a station is measured using a peak reading wattmeter to ensure that one station is in compliance with the power output permitted as per the license.

Oscilloscope This electronic test instrument is used to observe wave forms and voltages on a cathode-ray tube. It displays time on the X-axis and amplitude on the Y-axis and the intensity of the CRT spot along the Z axis. Different types of oscilloscopes are available at http://eham.net/.

Audio Wave Modulation The functioning of a radio may be a perplexing thing for a beginner. Voice produced in front of a microphone is heard using another radio which is placed at a different location. How does this happen? Modulation is the process of merging a radio signal with an information signal. For modulation to happen a carrier must be available. It is this carrier signal that transmits the information to the desired destination. Morse Code Modulation Morse code turns off and on an RF carrier in order to transmit a simple code alphabet. This is also called continuous wave (CW).


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Chapter 8 Elementary electricity “Smoking kills. If you’re killed, you’ve lost a very important part of your life.” ~ Brooke Shields, actress

‘God of Small Things’ It is always best to start small. One of my uncles who introduced me to the great hobby of amateur radio used to say that it’s the basics that make a man. Have you ever analyzed a flashlight? This is the best way to begin. A bulb is connected across two cells in a series. The metal switch contacts of a sliding switch make the command for the bulb to start its duty. This tiny thing can sometimes ruin the flashlight.


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Let’s move on to the circuit diagram of a flashlight.

Two cells of 1.5 volts are connected to a lamp with a switch in between. The lines in this schematic diagram represent the metal conductors which connect the system together.

Points to Remember A circuit is a closed conducting path. In the case of a flashlight, if the switch is not closed, then the circuit is not complete. When the metal parts of the switch fail to make contact, the circuit becomes incomplete. Cells Connected in Series

The current in the circuit should flow to make the lamp glow. How does this happen in a flashlight? The voltage or potential difference V pushes the current to flow. Two


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cells of 1.5 V, connected in series will provide 3 V, while three cells will provide 4.5 V (see the figure). A battery consists of two or more cells. The higher the voltage, the brighter the lamp will be. Cells can also be connected in parallel. Cells Connected in Parallel

A single cell may provide some current for a long time. If you connect the cells in series, it may increase the voltage, but will not have any effect on its life. A parallel connection guarantees a longer life.

The Direction of Current Flow As evident from the figure, the battery or cell has two terminals, one is positive while the other is negative. Conventionally, the current is considered to flow from the positive terminal to the negative terminal. Conventional current is often used to designate this current. The arrows in the circuit diagrams always point in this direction. This is the direction of flow of positive charged particles. When the charge carriers are negatively charged electrons, the flow direction will be opposite to the direction of conventional current. In electronic systems, charge carriers can be both positive and negative materials. The holes and electrons found in the transistors are examples of the coexistence of both positive and negative charge carriers in the same system.


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What Is Electric Current? If two bodies are connected through a conducting wire, electrons will flow from the negatively charged body to the positively charged one. This flow of electrons is called electric current. The electric current will continue to flow as long as the ‘excess’ and ‘deficit’ of electrons exist in the bodies. The electrons move around the nucleus of an atom in different orbits. The electrons in the inner orbits are tightly bound to the nucleus. As they move away from the nucleus, this binding goes on decreasing so that electrons in the last orbit (called valence electrons) are quite loosely bound to the nucleus. In certain substances, especially metals, the valence electrons are so weakly attached to their nuclei that they can be easily removed or detached. These electrons are called free electrons. The free electrons move at random from one atom to another in the material. Since a small piece of metal has billions of atoms, there are a large number of free electrons present. The SI unit of electric current is coulomb/sec, which is called ampere.

"Imagine if every Thursday your shoes exploded if you tied them in the usual way. This happens all the time with computers, and nobody thinks of complaining." ~ Jeff Raskin

Properties of Electric Current 1. The actual direction of current is from the negative terminal to the positive terminal through the part of the circuit external to the cell. However prior to the electron theory, it was assumed that current flowed from positive terminal to the negative terminal of the cell via the circuit. This convention is so firmly established that it is still in use. This assumed direction is called conventional current. 2. Those substances, which have a large number of free electrons, will permit current flow easily. Such substances are called conductors (i.e. copper, silver, aluminum, etc). On the other hand, atoms of some substances have valence electrons that are tightly


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bound to their nuclei. Such substances will not permit the flow of electric current and are called bad conductors or insulators (i.e. glass, mica, etc). Conductors Any material that permits an electrical current to flow through it without difficulty is called a conductor. The most effective conductors in electric systems are those with a high degree of free electrons. As a result, metals are excellent conductors of electricity, while glass and wood are not. Materials used as conductors fall into one of four types: metallic conductors, ionic conductors, insulators and semi-conductors. •

Metallic conductors have a large number of free electrons, which facilitate the efficient transfer of electric current.

•

A solution that is highly ionic, or has a large number of free ions, is called an ionic conductor. It is a good conductor of electric current, like metal in its liquid or molten form. Salt water is an excellent example of an ionic conductor.

•

An insulator has a lesser number of free electrons and is a poor conductor. Insulators do not permit electric current to flow through them, and for this reason, they often surround conductors. Rubber, glass, and plastic are good examples of insulators.

•

A semi-conductor conducts electricity partially, as it behaves like a conductor at high temperatures, and an insulator at low temperatures. Semi-conductors control the movement of electrons in an electric current depending upon the structure of the material used to construct it. Careful placement of non-conductive “impurities” on a conductive surface directs the flow of electrons, enabling advanced electronics. A semiconductor is neither a conductor nor an insulator. All semiconductor materials originate from silicon. It is a component made of silicon and glass. Silicon in its purest form is a good insulator. In order to change the conductivity of the silicon, impurities are introduced, which changes the number of electrons in the lattice structure. This process is called doping. Missing electrons are called holes.


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Extrinsic Semiconductors – P and N Type Since intrinsic or pure germanium/silicon semiconductors are of no use as such, their conductivity is enormously enhanced by judicious addition of impurity atoms or doping. The resultant semiconductor is called a doped or extrinsic semiconductor. (a) Donor atoms: If an impurity atom is added to a pure semiconductor like germanium/ silicon atoms, these impurity atoms dislodge some of the germanium/silicon atoms. Each impurity atom donates a free electron and is therefore called donor atom. The doped semiconductor containing donor atoms is called donor type semiconductor or Ntype semiconductor, because its conductivity is mostly due to electron current. However, the crystal as a whole remains electrically neutral. The mobile electrons so donated are far in excess of the conduction electrons released by thermal breaking of covalent bonds and they are therefore called excess electrons. Hence, the conductivity of N-type semiconductor is fairly constant over a large temperature range (unlike a pure semiconductor). When an intrinsic semiconductor is doped, the result introduces allowable energy levels slightly below the conduction band. Since the impurity atoms are placed relatively far away from each other, no interaction takes place and a single basic discrete level forms the new allowable state. In silicon, the gap is 0.05 V below the conduction level. Hence at room temperature, almost all excess electrons donated get raised into the conduction band. In N-type semiconductor, electron-hole pairs are formed as in the pure crystal. But, because of the more numerous excess electrons, recombination is rapid and only fewer holes than in pure crystal are present. In an N-type crystal, holes are called the minority carriers and the electrons are called the majority carriers. The doped semiconductor behaves like a resistor (called bulk resistance) with enhanced conductivity due to doping. (b) Acceptors and P-type semiconductors: If a trivalent impurity like indium, boron and gallium is used for doping germanium, this results in the production of holes. Since the


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holes so created accept electrons, the dopant is called an acceptor type and the resultant semiconductor is called P-type semiconductor. Holes are the majority carriers and the electrons are the minority carriers in Ptype semiconductors. At room temperature, almost all acceptor atoms get ionized and the number of mobile holes equals the number of acceptor atoms.

Pn Junction Diodes Pn Junctions When a p-type semiconductor is suitably joined to an n-type semiconductor, the contact surface is called pn junction. The pn junction is of great importance because it is the control element for semiconductor devices. A thorough knowledge of the formation and properties of pn junction can enable you to understand the semiconductor devices.

Formation of Pn Junction Pn junction is fabricated by special techniques. One common method is alloying. In this method, a small block of indium (impurity) is placed on an n-type germanium slab. The system is then heated to a temperature of about 500°C. The indium and some of the germanium melt to form a small puddle of molten germanium-indium mixture. The temperature is then lowered and the puddle begins to solidify. Under proper conditions, the atoms of indium impurity will be suitably adjusted in the germanium slab to form a single crystal. The addition of indium overcomes the excess of electrons in the ntype germanium to such an extent that it creates a p-type region. As the process goes on, the remaining molten mixture becomes increasingly rich in indium. When all germanium has been re-deposited, the remaining material appears as indium button, which is frozen on to the outer surface of the crystallized portion. This button serves as a suitable base for soldering on leads.


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“More and more of our imports are coming from overseas.” ~ George W. Bush, president

Properties of Pn Junction Consider a p-type semiconductor having negative acceptor ions and positively charged holes and an n-type semiconductor having positive donor ions and free electrons. If both are made to form a junction, which is a perfect joint, (on atomic state) then n-type material has a high concentration of free electrons while p- type material has a high concentration of holes. Therefore, at the junction, there is a tendency for the free electrons to diffuse over to the p-side and holes to the n-side. This process is called diffusion. As the free electrons move across the junction from n-type to p-type, positive donor ions are uncovered and are robbed of free electrons. Hence, a positive charge is built on the n-side of the junction. At the same time, the free holes cross the junction and uncover the negative acceptor ions by filling in the holes. Therefore, a net negative charge is established on the p-side of the junction. When a sufficient number of donor and acceptor ions are uncovered, further diffusion is prevented. It is because now positive charge on n-side repels holes to cross from p-type to n-type and negative charge on p-side repels free electrons to enter from n-type to p-type. Thus a barrier is set up against further movement of charge carriers (holes and electrons). This is called potential barrier or junction barrier Vo. This field sets up a drift of charge carriers, which opposes the diffusion of holes or electron current. The net charge flow across the open circuited junction is zero. Thus the positive ions and negative ions are not neutralized over a region. Since this region is depleted of mobile charges, this region is called the depletion region.


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Transistors Transistor is actually a term to describe “transfer resistance.” The device consists of a silicon or germanium single crystal containing two p-n junctions. They are formed between the following layers of the semiconductor. Base -- a very thin layer forming the central region. Emitter and collector layers -- These two are on the opposite sides on the B layer and are of the same type. An ohmic or non-rectifying contact is made to each of the layers. The junction between the base and emitter is called the emitter junction and the junction between the base and collector is called the collector junction. The device is classified into two main types – PNP or NPN depending on whether the base material is N or P.

Vacuum Tubes In electronics, there are a lot of devices in which a stream of electrons is controlled by electric and magnetic fields. Since a vacuum is required in the form of an evacuated enclosure in which the electrons can move without collisions with gas molecules. These devices, called vacuum tubes or electron tubes in the U.S., are known as thermionic valves in Britain. These devices have been completely replaced by semiconductors in current practice. They are also called "receiving" valves, which comes from their use in radio receivers. In vacuum tubes, the electrons shift from the cathode (K), the negative electrode, to the anode or plate (P), the positive electrode. But, conventional current flows in the opposite direction. At the cathode, the electrons are liberated either by heat (thermionic emission) or by the bombardment of positive ions. This causes emission of electrons. As a result, some gas molecules may become ionized by collision with speedy electrons. When an electron is knocked off, a positive ion is left off. The positive ions move in the opposite direction of the electrons. However, their current is in the same direction, since they have opposite charges. Due to the usage of a very high vacuum, the effect of Ham Radio In Plain English

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positive ions in a receiving tube is very small. The electrons released by the thermionic cathode accumulate to form a negative space charge cloud around the cathode. It is so dense that if no electron is removed by attraction to the anode, the rate of emission is equal to the rate of return. As soon as the anode is made positive, some of the electrons are attracted to it out of the space-charge cloud, and a thermionic current results. A third electrode, the grid, placed between the cathode and the anode, closer to the cathode has also some part in the electric field at the space charge that controls the current. The grid is made of a spiral of fine wire and electrons can pass through without hindrance. When it is negative, it opposes the effect of the anode in creating an electric field, but does not attract any electron, and draws no current. If it is made positive, it increases the plate current, but draws some grid current to itself. The grid provides a sensitive control thus making the vacuum tube a powerful amplifying device.


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Chapter 9 Magnetism and Basic Electric Devices

“Now they show you how detergents take out bloodstains, a pretty violent image there. I think if you've got a T-shirt with a bloodstain all over it, maybe laundry isn't your biggest problem. Maybe you should get rid of the body before you do the wash.” ~ Jerry Seinfeld, comedian Electric Potential When a body is charged, work has been done. This work is stored in the body in the form of potential energy. The charged body has the capacity to do work by moving other charges either by attraction or repulsion. This ability of the charged body to do work is called electric potential. Electric potential= work done/ charge Potential Difference The difference in the potentials of two charged bodies is called the potential difference between them. Current will flow if potential difference exists. No potential difference means there is no current flow. It may be noted that potential difference is sometimes called voltage. The potential difference between two points is 1 volt.

Resistance The opposition offered by a substance to the flow of electric current is called resistance. Since current is the flow of electrons, resistance is the opposition offered by the substance to the flow of free electrons. This opposition occurs because the atoms and molecules of the substance obstruct the flow of these electrons. It may be noted that resistance is electric friction offered by the substance and causes the production of heat with the flow of electric current. The unit of resistance is ohm.


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Capacitors Capacitors can simply be defined as the circuit element, which stores electrons. Mostly they are used as rechargeable batteries to provide stable voltage. Other than this function, capacitors have many other uses in an electrical circuit. Capacitors are comprised of aluminum electrolytic, ceramic disk, tantalum electrolytic, ceramic disc, mica, and polypropylene. A capacitor mainly functions as: •

Dc blocking devices -- When a capacitor functions as a dc blocking device, it allows ac to flow, while blocking the dc.

•

Supply by-pass capacitor -- This capacitor, when used on a dc supply line, shunts (shorts) to ground any unwanted ac.

•

Reservoir bypass capacitor -- A capacitor, used in the output of a dc rectifier, is called a reservoir bypass capacitor when it smoothes out the power line ac pulses and acts as a reservoir between the charging pulses.

•

Emitter bypass capacitor -- Considered a combination of two models. Under the dc conditions, it operates as a transistor. Under ac conditions, it functions as an amplifier.

When a battery of certain voltage is connected to a capacitor, the capacitor gets charged depending upon the voltage and the value of the capacitance.


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With reference to the above figure, there is a flow of negative charges to the lower plate, thereby making the upper plate positively charged. The voltage of the fully charged capacitor will be equal to that of its source. The charged capacitor stores energy in the form of an electric field. A capacitor is comprised of two plates separated by an insulator. The value of the capacitance mostly depends on the total surface area of the plates as well as the distance between the plates. The unit of capacitance is farad. Farad is a large quantity and the unit of microfarad is used in most of the cases. If the value of the capacitor is high, then the stored energy will be large.


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Schematic Symbol for a Capacitor Different types of capacitors are shown below - Capacitors from left to right: polypropylene, adjustable trimmer cap, polyester, ceramic radial capacitor, and ceramic axial capacitor.

Equivalent Series Resistance of a Capacitor (ESR) Ideally a capacitor should have only capacitance. But practically all conductors will have some resistance. All conductors contribute a certain amount of resistance can be represented by a resistor in series with the capacitor. Capacitors of higher ESR values will allow only a lesser quantity of current to pass to the external circuit. Similarly equivalent series inductance (ESL) is the value of inductance connected in series with the capacitor. As the electrolytic capacitors consist of a large coil of flat wire, it will have some inductance.

“I want to have children, but my friends scare me. One of my friends told me she was in labor for 36 hours. I don't even want to do anything that feels good for 36 hours.” ~ Rita Rudner, comedian Film Capacitors Capacitors less than one microfarad usually contain a plastic type of insulator. They can also be metallized material bonded on to the plastic material. Film capacitors are illustrated below. Ham Radio In Plain English

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Electrolytic Capacitors Electrolytic capacitors are used for capacitance values higher then 0.47 micro farad. They consist of a paper material between two layers of aluminum foil. The below figure illustrates an electrolytic capacitor.


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Capacitor and Voltage A capacitor may have a surge voltage and a working voltage. Working voltage provides the value of the voltage the capacitor can withstand over time. A surge voltage depicts the value, which it can withstand for a shorter duration of time. Application of too much voltage can fail a capacitor.


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Electric Field An electrically charged object induces a force field around it, which can be detected and measured. These electric charges are capable of moving the electric charges in the field. An electrically charged object will have either a greater or smaller concentration of electrons than normal. This guarantees the existence of a difference of potential between a charged object and an uncharged object. This difference of potential produces an electric field. This field of force is normally represented by lines, which depict the paths along which the force acts. A large concentration of lines demonstrates a large electric force. Similarly lesser number of lines indicates a weak force. “Charlie Brown is the one person I identify with. C.B. is such a loser. He wasn't even the star of his own Halloween special.” ~ Chris Rock Alternating Current In a power station, the conventional method of producing electricity is by using a motor to spin magnetic wire coils. The electricity, thus produced will be fluctuating in nature by virtue of motor’s rotation. This is known as alternating current. As discussed earlier, the electric current can be transmitted, more effectively in the form of alternating current. Hence the electricity that arrives in homes is ac. One complete cycle of the signal occupies 360 degrees irrespective of the amplitude. The number of cycles-per-second is the frequency of the signal. This cycle is depicted using a sine wave. A signal may start at zero degrees and then reach its most positive value at 90 degrees, then come back to zero value at 180 degrees and continue to its most negative value at 270 degrees. It can then return to zero again at 360 degrees. This is one complete cycle.


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The frequency of the domestic supply in the U.S. is 60 cycles/second or 60 Hz. If the frequency is 50 Hz as in Australia, one cycle occupies 1/50th of a second or 20 milliseconds. Here the signal reaches its maximum positive value after five milliseconds, then goes down to its maximum negative value in the next five milliseconds. This complete cycle takes almost 20 milliseconds and repeats 50 times a second. In the case of a 60 Hz frequency, one cycle occupies 1/60th of a second or 16.67 milliseconds.

Magnetism Magnetism is a natural phenomenon that acts as a force to attract or repel specific substances, particularly metals. It is displayed by magnets and electric currents. Magnetism is ultimately a creation of electric charges and their movements.

Types of Magnets Any mass that produces an external magnetic field is called a magnet. A magnet’s force affects other magnets, electric currents and materials exhibiting magnetic properties. Magnets occur mainly in two varieties: permanent and excited. A permanent magnet is one in which the magnetic field is always on, and the possessing material is always magnetized. Permanent magnets are often made of ferromagnetic material; ferro refers to iron, which is a material that responds strongly to magnetism and is easily magnetized. However, not all ferromagnetic materials are iron. Ham Radio In Plain English

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Some alloys and ceramics actually produce better permanent magnets than iron. Permanent magnets may lose their magnetism if they are heated to an extreme, are subject to a demagnetizing field, or are exposed to shock. A temporary magnet (also known as an excited or induced magnet) is one in which the magnetic field may be turned on and off through an electric current from an outside source. Temporary magnets can be made from materials that do not respond strongly to magnetism by running electric current through a conductor to construct an electromagnet. Electric currents may also be used to supplement the magnetic power of a permanent magnet.

Magnetic Poles and Forces All magnets have two poles, which is where the majority of their magnetic force is. Like electric charges, there are positive and negative poles, and similar poles repel one another while dissimilar poles attract one another. The north or north-seeking pole of a magnet is called so because it is attracted to the Earth’s North Pole. A magnet’s south or south-seeking pole is attracted to the South Pole. The Earth is itself a large, permanent magnet resulting from the molten iron core that creates an electric current with its movement. Because the Earth is a magnet, it is possible to detect its magnetic field using a compass, or a thin, rotating magnet. The compass magnet will rotate so that its poles are aligned in the opposite direction of the Earth’s, as similar poles repel one another.

Magnetic Fields Like electric charges, magnets create a field of magnetic force around their poles. These magnetic fields contain the kinetic energy of the poles’ charges that can be applied to other objects as they approach the magnet and enter its magnetic field.


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Figure shows the B-H characteristics for a ferromagnetic material where B is the magnetic flux density and H is the magnetic field. Operation follows the line, in the direction indicated by the arrow.

A magnetic field follows a path around the magnet according to certain lines of force, called lines of induction. The lines of induction appear similar to the electric field Ham Radio In Plain English

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surrounding a dipole, circling the magnet to connect its north and south poles. A magnetic field is formed around a conductor, whenever a current flows through the conductor. Unlike the electrical lines, magnetic lines are not drawn between the rods. The magnetic lines of force are drawn at right angles to the direction of current flow. The left hand rule is used to determine the direction of magnetic line of force. When one holds the conductor in the left hand as shown in the figure, the fingers will point in the direction of magnetic line of force.

A magnetic field is not easily measured quantitatively. The easiest way to identify a magnetic field is to observe whether certain metals are attracted to a particular object or medium. However, a weak magnetic field may not be visible this way. One way to identify even a weak magnetic field involves iron filings, a sheet of paper and the object believed to be a magnet. If the iron filings are spread on the paper and a magnet is placed underneath the paper, the filings will arrange themselves in a pattern that outlines the magnet’s lines of induction. Ham Radio In Plain English

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Circuit Theory A circuit is a corridor through which an electric or magnetic current travels, or is anticipated to travel. The essential components of a circuit include a power source, two connecting wires to conduct the current, and a load to receive the energy. If the connections between the power source and the load are complete and correct, the current will flow, creating a closed circuit.

Types of Circuits Most circuits occur as series or parallel circuits. Series circuits connect all components using a single length of wire, and are of the simplest circuit construction. In a series circuit, the power source and load follow one another in a series, so that the electric current must travel through the first component before it can be passed on to the second and successive components. The string of Christmas tree lights that refuses to work if one bulb fails is an example of a series circuit. This demonstrates one of the pitfalls of a series circuit: that the circuit as a whole will not function if a single component fails. Another problem is that resistance increases as the number of components on the circuit increases. In a parallel circuit, the components are connected individually to the power source by lengths of wire that mirror one another, or are parallel to one another. Each component in a parallel circuit receives the same amount of voltage independent of the other components. The disadvantages of series circuits reflect the advantages of parallel circuits. Parallel circuits do not fail as a whole if a single component in the circuit fails, and the amount of resistance on a parallel circuit does not increase as components are added.

Circuit Components Circuits can contain many different components besides the essential power source, wires and load. If a circuit’s power source is a direct current, a battery will be a major component.


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•

Battery -- Batteries produce electric current through a chemical reaction that generates an excess of electrons at one terminal (pole), while creating a deficiency of electrons at the second terminal (pole). As a result, a battery connected to a closed circuit will attempt to equalize this imbalance by sending an electric charge through the connecting wires to the deficient terminal.

•

Switch -- A circuit must be closed in order for its electric current to flow; to exercise control over the electric current, a switch may be introduced into the circuit. A switch is an opening in the circuit that can be opened to prevent a flow of electricity, or closed to enable an electric flow. Switches are useful in conservation of energy, since they permit the flow to be broken, preventing unnecessary energy use.

"Adults are always asking kids what they want to be when they grow up because they are looking for ideas.” ~ Paula Poundstone, comedian

Sometimes, a power source in a circuit provides more energy than the load requires. To decrease the amount of electrical current, a resistor may be added to the circuit. •

Resistor -- A resistor introduces additional resistance to an electric flow by converting electricity into heat. Some resistors are variable, which means the amount of resistance they introduce to a circuit can be changed.

The Objective of a Resistor The duty of the resistor is to limit the flow of current. Normally a resistor is connected in a series with a light emitting diode.


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Symbols used to denote resistors vary by continent. A zigzag symbol is found in both the U.S. and Japan while a box symbol is popular in the UK and Europe.

A carbon film resistor is shown below.


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The advantages of carbon film resistors are that they are easily available and are quite inexpensive. Their accuracy ranges are within ± five percent to ±10 percent of their marked values. Metal oxide resistors have a better accuracy within ± one percent of their nominal value. Light Dependent Resistor A light dependent resistor together with its circuit symbol is demonstrated below.


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A cadmium sulfide track functions as the light sensitive part of the LDR. As the light energy falls on the light sensitive part, extra charge carriers are released in this material thus causing the resistance to decrease. This induces an increase in the level of illumination.

Capacitor We have already dealt with capacitors in detail. Here is a brief explanation of the capacitor. A capacitor is a component that can be added to a circuit to regulate voltage by storing a charge in an electric field between two plates or surfaces that are positioned close together, but do not touch. A capacitor will store electricity in its field until the opening between the two plates is closed and the capacitor is allowed to discharge the energy it has stored. The storage of energy in an electric field allows the capacitor to discharge, even if a switch disconnects the power source. A diode is a circuit component that permits an electrical current to flow in a single direction only. On one end, the diode has a high resistance to an electrical current, and on the other end, has a low resistance to an electrical current. Consequently, a diode is often used to convert alternating current into direct current. Light-emitting diodes (LED) produce light when an electrical current is flowing in the right direction. The light of an LED is used for entertainment, but also provides a useful source of information about circuits.


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Different components in a PCB An inductor is a coil of wire added to a circuit to create a magnetic field. The magnetic field stores energy by resisting voltage changes, much like a capacitor.


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A transformer is used with alternating current to vary the current’s voltage through electromagnetic induction, or the change in electric potential achieved by altering a surrounding magnetic field. The difference between the voltage supplied to the transformer and the voltage produced by the transformer is directly related to the number of coils belonging to the inductor. If the primary or initial winding of the inductor has more coils than the secondary, the transformer will produce less voltage than was supplied to it. Conversely, if the primary or initial winding of the inductor has fewer coils than the secondary, the transformer will produce more voltage than was supplied to it.


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Temperature Sensors Temperature sensors are sensitive to temperature. When the resistance of a resistor decreases with the rise in temperature, it is called a negative temperature coefficient thermistors or an ntc thermistor. A positive temperature coefficient thermistor or a ptc thermistor shows an increase in resistance with temperature.

Microphone A microphone is also termed as sound sensor. The figure given below shows a cermet microphone. Cermet is a combination of both ceramic and metal. The sound sensitive part is produced using a mixture of these materials.


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Switch

When a switch is pressed, a voltage signal is usually generated. This voltage signal sets off the circuit in to action. This can be accomplished in two different ways.

The pull down resistor makes the output voltage, Vout, to be of a low value, except when the switch functions. When the switch is pressed, a high voltage is delivered. The pull up resistor makes the output voltage of a high value, except when the switch functions. When the switch is pressed, a low voltage is delivered.

"Outside of the killings, Washington has one of the lowest crime rates in the country." ~ Marion Barry, former Washington D.C. mayor


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Fuse A fuse is a protection device used in a circuit. If there is any malfunction in the equipment, the fuse burns and melts, thus cutting off the power to the circuit. After correcting this problem, the device can be again put into operation. Special care should be taken while fixing a new fuse. The fuse must have the same current ratings. When replacing a fuse with one of lower rating, the fuse will be blown off as soon as it is replaced. If the fuse is of higher rating, it can cause an accident. Voltmeter Voltmeter is a device used to measure the voltage of a portion of a circuit. When measuring, the voltmeters are connected “parallel” across the circuit. Ammeter Ammeter is used to measure current in a circuit. Ammeter shows the current flowing in amperes through the circuit. The ammeter is placed in series with the circuit. Multimeter A multimeter is considered multipurpose equipment, which can be used to measure the current, voltage as well as resistance. Generally used electrical symbols are given below.

ac supply

amplifier


aerial

ammeter

battery

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Capacitor

d c supply

cell

diode

earth

fuse

led

loud speaker

mic

motor


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ohmmeter

photodiode

! transformer

!

! npn transistor

Circuit Equations Ohm’s law explains the relationship between a current, its voltage, and resistance, stating that a circuit’s current is directly proportional to its voltage and inversely proportional to its resistance. This relationship can be described with the following equation: E = (I) R Where E represents voltage, I is the amount of current and R is equivalent to the amount of resistance in a circuit. Joule’s law explains the relationship between heat and electricity as one converts to the other. It states that the amount of heat created by an electrical conductor holding a current is directly proportional to the amount of the conductor’s resistance, multiplied by the square of the current itself, illustrated by the following equation: P = I2 (R) Where P is equivalent to the amount of heat, I represents the circuit’s current and R is the amount of resistance.


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Kirchhoff’s laws describe energy requirements for circuits, specifically voltage and circuit requirements. They are the Law of Voltage and the Law of Currents. The Law of Voltage states that all voltages in any closed circuit must equal zero. The Law of Currents states that at any node, or current junction, the sum of currents entering must equal the sum of currents exiting.


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Chapter 10 Transmission of Electricity "I tell you, that Michael Jackson is unbelievable! Isn't he? He's just unbelievable. Three plays in twenty seconds." ~ Al Gore, former vice president, commenting on Michael Jordan Structure of Electric Power Systems Generating stations, transmission lines and the distribution systems are the main components of an electric power system. Generating stations and a distribution system are connected through transmission lines, which also links one power system (grid area) to another. A distribution system connects all the loads in a particular area to the transmission lines.

A Power Transmission Line


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For economical and technological reasons, individual power systems are organized in the form of electrically connected areas or regional grids (also called power pools). Each area or regional grid operates technically and economically independently, but these are eventually interconnected to form a national grid (which may even form an international grid) so that each area is contractually tied to other areas in respect to certain generation and scheduling features. Electric power is generated at a voltage of 11 to 25 KV, which then is stepped up to the transmission levels in the range of 66 to 400 KV (or higher). As the transmission capability of a line is proportional to the square of its voltage, research is continuously being carried out to raise transmission voltages. Some countries are already employing 765 KV. For very long distances (over 400 miles), it is economical to transmit bulk power by DC transmission. It also offers obvious technical problems associated with very long distance AC transmission. The DC voltages used are 400 KV and above, and the line is connected to the AC systems at the two ends through a transformer and converting/ inverting equipment (silicon controlled rectifiers are employed for this purpose). Several DC transmission lines have been constructed in Europe and the U.S. The conductor system by means of which electric power is conveyed from a generating station to the consumer’s premises may, in general be divided into two distinct parts (i.e. transmission system and distribution system). Each part can again be sub-divided into two primary transmission and secondary transmission, and similarly, primary distribution and secondary distribution, and then finally the systems of supply to individual consumers. It is a common practice nowadays to interconnect many types of generating stations by means of a common electrical network and operate them all in parallel. This combination of generating stations forms what is known as a power system. The various elements of such systems like generating stations, transmission lines, the substations, feeders, and distributors become tied into a whole by the integrated process of continuous generation and consumption of electric energy. A system network (or


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grid) is the name given to the part of the power system that consists of the substations and transmission lines of various voltage rating. Distribution The distribution system may be divided into feeders, distributors, sub-distributors and service mains. As already explained, feeders are the conductors, which connect the sub-station (in some cases the generating station) to the distributors serving a certain allotted area. Various tappings are taken from distributors. The connecting link between the distributors and the consumer terminals are the service mains. There is an essential difference between a feeder and a distributor. The current loading of a feeder is the same throughout its length, but the distributor has a distributed loading which results in variations of current along its entire length. No direct tappings are taken from a feeder to a consumer’s premises.

Transmission and Distribution Today, all production of power is AC power, and nearly all DC power is obtained from large AC power systems by using converting machinery like synchronous or rotary converters, solid-state converters and motor-generator sets. There are many sound reasons for producing power in the form of alternating current rather than direct current. 1. It is possible, in practice to construct large high-speed AC generators of capacities up to 500 MW. Such generators are economical both in the matter of cost per kWh of electric energy produced as well as in operation. Unfortunately, DC generators cannot be built of ratings higher than 5 MW because of commutation trouble. Moreover, since they must operate at low speeds, it necessitates large and heavy machines. 2. AC voltage can be efficiently and conveniently raised or lowered for economic transmission and distribution of electric power respectively. On the other hand, DC power has to be generated at comparatively low voltages by units of relatively low power ratings. There is no economical method of raising the DC voltage for transmission and lowering it for distribution. Ham Radio In Plain English

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Chapter 11 Electromagnetic Waves and Radio Waves "You teach a child to read, and he or her will be able to pass a literacy test.'' ~ George W. Bush, president Electromagnetic Waves The main constituents of an electromagnetic wave are an electric field and a magnetic field. Generally, electromagnetic fields are an orientation of horizontal and vertical line of force at right angles to each other. The electromagnetic field (E) and the magnetic field (H) together form these lines of force, which in turn constitute the electromagnetic force. It is this electromagnetic field that makes the groundwork for the transmission and reception of electromagnetic waves through space. We have already dealt with the basics of electric and magnetic fields.

Basics of Wave Motion When referring to the wave in the figure, one complete cycle of the wave is represented by points ABCDE. As evident from the figure, this wave has maximum points on both sides of the reference line. The combination of the area covered by the portion above the reference line (ABC), and one portion below the reference line (CDE), completes one cycle of the wave. The peak of the positive part is sometimes called the top or the crest. The peak of the negative part is the bottom or the trough.

Wavelength A wavelength is the distance traversed by one cycle of a wave. Wavelength is inversely proportional to the frequency. Hence, at extremely high frequencies, wavelength will be very small, and at extremely low frequencies, wavelength will be very large (can extend to many miles). The Greek letter lambda () is used to denote wavelength. Ham Radio In Plain English

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Amplitude The altitude of the peak above the reference line is known as the amplitude of the wave. It is possible for two waves to have the same wavelength, but different amplitudes.

Frequency The number of cycles of a wave train in a unit of time is called the frequency of the wave train. The unit of frequency is cycles/second or hertz. Consider that 10 waves pass a point in one second. The frequency of the wave is 10 cycles/second. If we know the velocity and frequency of a wave, we can determine the wavelength of the wave using the following equation: = v/ f, where is the wavelength, v the velocity of propagation and f the frequency of the wave.

Radio Waves A radio wave is an energy wave generated by a transmitter. It is a combination of both electrical field and magnetic field, better known as electromagnetic field. The standard shape of the wave generated by a transmitter is that of a sine wave. The frequency of a sine wave is the number of cycles that are completed in one second. The frequencies between 3,000 hertz (3 kHz) and 300,000,000,000 hertz (300 GHz) are called radio frequencies. For convenience, the radio frequencies are divided into bands. One band is 10 times higher in frequency than the preceding one.

Units of Frequency Frequencies of the amateur radio are always expressed in kilo (thousand), mega (million) or giga (billion) hertz.


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Bandwidth Bandwidth explains how much space a specific signal takes up. The unit used for measuring bandwidth is kilohertz. A large bandwidth denotes that it contains more information and occupies more room in an amateur radio band. The frequency band is tabulated below.

FREQUENCY

DESCRIPTION

TERMINOLOGY

3 to 30 KHz

Very low

VLF

30 to 300 KHz

Low

LF

300 to 3000 KHz

Medium

MF

3 to 30 MHz

High

HF

30 to 300 MHz

Very high

VHF

300 to 3000 MHz

Ultra high

UHF

3 to 30 GHz

Super high

SHF

30 to 300 GHz

Extremely high

EHF

If a particular frequency is the whole number multiple of a smaller basic frequency, then that frequency is referred to as the harmonic of the basic frequency. The basic frequency is often called the first harmonic or fundamental frequency. A second harmonic is the frequency which is twice as great as the fundamental frequency and the terminology repeats for the third, fourth, etc. The time required for one complete cycle is known as the period of a radio wave. For a sine wave of frequency of four hertz, each cycle has a period of one-fourth of a second. The frequency of a radio wave is inversely proportional to the period. A wavelength is horizontal distance transposed by one full cycle of a radio wave at any given instant. The velocity of a radio wave is equivalent to the speed of light (186,000 miles per second). The speed of the radio wave is independent of the frequency. A two megahertz wave travels through the space with the same velocity as a six megahertz wave. Ham Radio In Plain English

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The plane in which the E field propagates with respect to the Earth is the plane of polarization of radio wave. If the E field component of the radio wave propagates in a plane perpendicular to the Earth's surface (vertical), the radiation is said to be vertically polarized. If the E field radiates in a plane parallel to the Earth's surface (horizontal), the radiation is said to be horizontally polarized. In order to maximize the quantum of energy absorbed from the electromagnetic fields, the antenna at the receiving end must be located in the plane of polarization. This explains the placement of the conductor at the antenna at right angles to the magnetic line of force moving through the antenna and parallel to the electric lines effectuating maximum induction. The right hand rule is used to determine the direction of wave propagation. The rule states that if the thumb, forefinger and the middle finger of the right hand are extended so that they are mutually perpendicular, the middle finger will point in the direction of the wave propagation, if the thumb points in the direction of the E field and forefinger points in the direction of H field. The wave always propagates in the direction away from the antenna. In the atmosphere, radio waves can be reflected, refracted and diffracted. Depending upon the obstructing object, the radio waves can be reflected to a different extent. The earth’s surface is an excellent reflector of radio waves. Metals with good electrical conductivity are excellent reflectors. When the radio waves move from one medium to another, with differing velocity of propagation, the bending of this wave occurs. This is known as refraction. When a radio wave enters a highly charged area of the atmosphere, refraction will take place. The part of the wave that enters first will travel at a greater speed than that which has not yet entered. This sudden change of velocity causes the wave to bend towards the earth, which is called refraction.

The Factors Affecting Radio Waves The characteristic of the medium in between the transmitting antenna and the receiving antenna often affects the propagation of radio waves in one way or another. The atmospheric condition varies with height, changes in geographic locations, and with the changes with respect to day/night and seasons. The information on basic division of the earth’s atmosphere is always helpful for an amateur radio enthusiast.


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Chapter 12 A Peep into the Atmosphere "Whenever I watch TV and see those poor starving kids all over the world, I can't help but cry. I mean I'd love to be skinny like that but not with all those flies and death and stuff." ~ Mariah Carey What Is Atmosphere? We live at the bottom of an ocean – an ocean of air. All around us this ocean, called the atmosphere, presses in upon us and affects us in everything we do. We breathe its gases and they keep us alive. We communicate by speech. Fuels burn through vibrations. Particular layers shield us from harmful radiations from the sun. Even at heights of tens of kilometers, it is thick enough to arrest the flight of meteorites and cause them to burn up before reaching the earth’s surface. It is colorless, tasteless and odorless, but it enables us to exist. This vast ocean reaches several hundred kilometers above our heads, but on a world scale, it is like a thin envelope. The earth’s atmosphere is divided into three regions: troposphere, stratosphere, and ionosphere.

Troposphere. The troposphere, the region in contact with the earth’s surface and where weather occurs, is characterized by a decrease of temperature with increasing altitude. The troposphere extends from the surface of the earth to a height of about 3.7 miles (6 km) at the North Pole or the South Pole and 11.2 miles (18 km) at the equator. It is the layer in which we live and function. It contains more than 75 percent of the earth’s atmosphere. Nearly all of the earth’s weather conditions – including most clouds, rain, and snow – occur in this layer. Thus scientists forecast the most aerosols and water vapor in the air. Jet streams blow in the upper part of the troposphere. The temperature of the troposphere decreases about 6.5 0C for every kilometer of increase in altitude.


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The temperature stops decreasing at the tropopause, the upper boundary of the troposphere. The temperature in this region decreases rapidly with altitude. Clouds form, and there may be much turbulence because of variations in temperature, density, and pressure. These conditions have a great effect on the propagation of radio waves.

Stratosphere Above the troposphere is the stratosphere. The troposphere and the stratosphere show distinct circulating systems. Whereas vertical motions prevail in the former, motions in the latter are largely confined to the horizontal. Very little moisture enters the stratosphere and clouds are rare. Airline pilots prefer to fly in the stratosphere to stay above the weather disturbances that occur in the troposphere. The stratosphere usually has a lower layer of nearly steady temperature and an upper layer in which the temperature increases with altitude. The upper layer contains most of the atmosphere’s ozone. The ozone heats the air thereby absorbing ultraviolet rays from the sun. The temperature throughout this region is almost constant and there is little water vapor present. The stratosphere has relatively little effect on radio waves because it is a relatively calm region with little or no temperature changes.

Ionosphere The ionosphere extends upward from about 31.1 miles (50 km) to a height of about 250 miles (402 km). The air in the ionosphere is extremely thin. More than 99.99 percent of the atmosphere lies below it. The chemical composition of the thermosphere differs from that of the other atmospheric layers. In the lower regions of the thermosphere, many of the oxygen molecules in the air are broken into oxygen atoms. The outer layer of the thermosphere consists chiefly of hydrogen and helium. Ionosphere is completely exposed to the sun’s radiation, which heats the thin air to extremely high temperatures – attaining a maximum value of more than 1,000 degree Celsius at about 250 miles. This usually happens during solar storms when more radiation and particles strike the atmosphere. When this happens, the radiation ionizes some of the molecules and atoms of the air. This is why this region is known as ionosphere. The ionosphere Ham Radio In Plain English

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plays an important part in long distance radio communication. It reflects back to the earth radio waves that would otherwise travel into space.

------------------------------------------------------------------------------------------------------------------------- ### --This concludes Ham Radio In Plain English. I hope you found the information helpful and I wish you many hours of happy broadcasting!

Randy Pryor Also available from Randy Pryor:

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