HAM Radio


Ever since Marconi and Jagadish Chandra Bose transmitted the first radio signals about one hundred years ago, amateur experimenters have played an important role in the development of radio communication.

In the first part of the twentieth century, radio experimentation by members of the public was tolerated by the governments and radio amateurs were confined to bands which were considered ‘useless’ for commercial or public use. After World War II, the vast amounts of surplus equipment, which became available, greatly stimulated amateur radio.

Now, new developments in computers, microcircuits and materials offer amateur radio a bright new future.

One of the most fascinating aspects of amateur radio, is making radio contacts with other radio amateurs all over the world. And sometimes in remote locations.

Very often friendships for life are made between radio amateurs, carrying out experiments with various equipment and modes, and often with advanced communication techniques.

The Shortwave Listeners ( SWL ), may also contact these amateurs by sending them a QSL card, a postcard-size report which confirms the reception of a radio contact made by two amateur stations.

A large percentage of the amateurs prefer experimenting with components and circuits. Others use the computer as an entry point to the hobby. A great variety of equipment is used.

Many of the older radio amateurs will perhaps recall with nostalgia ‘the good old days’ before the existence of computers. Back then the only equipment in a ‘radio shack’ was a radio receiver, a transmitter, and a keyer for sending messages in Morse code (CW).

In many countries, radio amateurs have founded Amateur Societies which provide forums to exchange ideas and also to protect the interests of the Radio Amateur Service. This is, in principle, not very different from the role of learned societies which cater for the interests of electronics professionals.

Furthermore, since many professional electronics engineers and technicians are also radio amateurs, the distinction between ‘amateur’ and profession can become very much blurred.

Who are Radio Amateurs?

Those who pass a written exam – Morse code is NOT required – is issued a license by the FCC. This license is unique, and is issued by the licensing authority, usually a government department.

The callsign is issued by the FCC at the time of granting a license.

A license can only be obtained after successfully passing an amateur radio examination, also conducted under the scrutiny of the licensing authority. (Please see the VE TESTING page on this site). The license permits the radio amateur to carry out experiments in communications by radio, subject to a set of conditions which can be quite complex

What is a ShortWave Listener (SWL)?

Many radio amateurs started their hobby listening to shortwave radio. Starting with radio broadcasts from distant countries, they become interested in receiving weak or distorted radio signals on congested frequency bands. A very popular aspect of his hobby is to monitor radio communications on the many frequency bands, allocated by international agreement to amateur radio.

Receiving other kinds of radio transmission, like standard time signals and police scanners, may sometimes be very interesting. The reception of signals from radio beacons can provide useful information about the propagation of radio waves.

The SWL individual very often builds his own equipment, from antennas to receivers and signal processors. And with the availability of personal computers, other communication modes, such as weather maps, radio telex bulletins, slow-scan television and PSK31 have become increasingly popular.


Radio communication – including communications by radio amateurs – is regulated on an international level by the International Telecommunication Union, ITU, a United Nations body. This organization has assigned to each country in the world a unique code to identify the radio stations which it administers. The code consists of a short number of characters.

Each amateur radio station is assigned a station identifier – the CALL SIGN – which is unique for the entire world.

The call sign consists of two or three parts. For instance: The callsign W9PVR is composed of a prefix (W), a number (9) representing the call are a in the U.S. in which the radio station is located, and the suffix (PVR). In the case of W9PVR, the call is a “vanity” call especially requested by the Pine Valley Repeater Amateur Radio Club. So:

  • A prefix, denoting the administration which issued the license. This is often the country of residence. It may also indicate the type of amateur station, club station, network, etc. The prefix usually comprises one or maximum two symbols of a combination of letters and numbers. The ITU maintains a large list stating the countries and their callsigns, a list that is regularly updated due to the changing political situation. By convention a number follows the prefix to indicate that the callsign belongs to an amateur station.
  • The suffix is group of one to three letters, identifying the amateur radio station uniquely.
  • Another suffix to the callsign may be used to indicate a special situation, such as

/M indicates a MOBILE station installed in a vehicle.
/A indicates a radio station operating from a TEMPORARY location.
/P indicates that the radio equipment is being used as PORTABLE equipment.

  • Sometimes it is possible for an amateur to operate his station on the territory of a country other than the one which initially issued his permanent license. In these cases his permanent call may be preceded by the prefix of the prefix of the host country.

Identifying Shortwave listeners:

In some countries short wave listeners are also issued with an identifying code. The identification is assigned by the association with which they are affiliated.

In the Netherlands, for instance, the issuing government body distributes NL-numbers. In Belgium distributes ONL-numbers and the GOS-listeners (from the former Soviet Union) are identified by U-numbers. So, you may be confronted with ‘NL8800’, ‘ONL2820’ or ‘UA3-170-112’, indicating SWL’s from Holland, Belgium and GOS respectively.

ARRL Call District Map


US Grid Square Map


UTC Conversion Chart


Radio Communication Techniques and Methods

Telegraphy ( Morse code ):

Switching the transmitter on and off using predetermined sequences is the oldest technique to send signals by radio. Morse code is still very popular under harsh conditions. It is a fact that CW signals will be heard when other modes cannot. An appreciation of this communication mode is the fact that many amateurs are learning Morse code despite it no longer being required to upgrade to a higher license.


The transmitter is used to transmit speech, such as is used for almost all radio broadcasts.


What is PSK31 you may ask? It’s simple, and yet it’s not. Translated literally, it’s an acronym for “Phase Shift Keying, 31 Baud”. PSK31 is a form of modulation (or “mode”) that offers a new and higher level of performance in conversational communications (keyboard-to-keyboard) that we “hams” (amateur radio operators) can enjoy. And it’s been made instantly usable by all of us, due in part to the proliferation of the personal computer, and in part to the superb and generous efforts of some very talented ham/computer programmers.

Amateur television ( ATV and Slow Scan TV ):

Pictures can be transmitted using a variety of techniques

Mobile and portable use:

Attention is paid to weight and size of the equipment, power consumption. In most populated area’s many unmanned repeaters are operated, placed in a high location with good coverage to support communications between mobile stations which could otherwise not contact each other.

Long distance communications ( DX ):

Knowledge of propagation aspects, forecasts and operating experience are important ingredients for successful radio communications over long distances.

Expeditions to remote locations:

In their endeavor to provide radio communication with all parts of the world, radio amateurs organize to communicate to remote and exotic places. In addition to highly reliable equipment, these expeditions require creativity and well developed organizing talent.

Moon Reflections ( EME ):

Bouncing radio signals is presently the ultimate in radio communication technology. The gap between two amateur stations is bridged by bouncing radio signals off the moon. This activity requires a high level of technical skill and dedication.

Amateur satellites:

The first amateur satellite was launched in 1961. Now, the latest generation of satellites designed and built by radio amateurs provide earth-to-space links. Also on most missions of the ISS (International Space Station) one of the crew members is a licensed amateur radio operator.

Meteor Scatter:

Long distance contacts can be made by reflecting radio waves off the ionized trails left by meteors as they travel through the ionosphere.

Radio Telex ( RTTY en AMTOR ):

These techniques are mostly used for transmitting information bulletins. The bulletins can be received with uncomplicated equipment.

Packet Radio:

This involves sending and receiving E-mail, by radio, exchange of computer programs and distributions of radio bulletins. A world wide radio packet-network is maintained by radio amateurs. The extra equipment is more complex then is required for radio telex. Using packet radio, the Dutch Packet Network is very active.

Digital techniques:

Digital techniques play an ever increasing role in amateur radio. New stimuli are being given to the development of noise suppression systems, speech enhancement, filtering and modulation techniques, frequency generation.


APRS is a real-time tactical digital communicatons protocol for exchanging information between a large number of stations covering a large (local) area. As a multi-user data network, it is quite different from conventional packet radio.

  • APRS is different from regular packet in four ways. FIRST by the integration of maps and other data displays to organize and display data, SECOND, by using a one-to-many protocol to update everyone in real time, THIRD, by using generic digipeating so that prior knowledge of the network is not required, And FOURTH, since 1997, a worldwide transparent internet backbone, linking everyone worldwide. APRS turns packet radio into a real-time tactical communications and display system for emergencies and public service applications (and global communications). Normal packet radio is useful in passing bulk message traffic (Email) from point- to-point, but it does not do well at real time events where information has a very short life time and needs to get to everyone quickly.
  • APRS is a LOCAL RF network. Although the Internet monitors APRS worldwide, this is not the primary objective. But like all of our other radios, how we use APRS in an emergency of special event is what drives the design of the APRS protocol. Although APRS is used 99% of the time over great distances, and benign conditions, the protocol is designed to be optimized for short distance real-time crisis operations on RF.
  • APRS provides universal connectivity to all stations in the net by avoiding the complexity and limitations of a connected network. It permits any number of stations to exchange data just like voice users would on a voice net. Any station that has information to contribute simply sends it, and all stations receive it and log it. Secondly, APRS recognizes that one of the greatest real-time needs at any special event or emergency is the tracking of key assets. Where is the Event Leader? Where are the emergency vehicles? Whats the Weather at various points in the County?
  • To answer these questions, APRS transmits and captures the location and status of all stations. It can be used over any 2-way radio system including HAM, CB, Marine Band, etc.
  • APRS is on 144.39 throughout the North American Continent. Other countries may use other frequencies. Check locally.
  • Here are some interesting sites as suggested by Chris, KC9CMD
    • Information about APRS
    • APRS SSID Information
    • see a live look at APRS for the Richland Center area

      • With the explosive growth of computers and miniaturized electronic systems, one may ask if there is still a future for amateur radio. The answer is an unqualified YES.
      • It is also pointed out that commercially available transceivers can outperform the home-made equipment at considerably lower cost. Furthermore congestion in the amateur frequency bands and interference caused by illegal broadcasting stations (often funded by national sources), make it hard for the beginning amateur operator to make radio contacts.
      • The advent of multimedia computers, low cost microwave transistors, complex integrated circuits and new materials and components, has expanded possible remedies a great deal.
      • Special digital modulation techniques, such as ‘spread spectrum’, can be used for point-to-point transmissions. A new domain for people who prefer to replace complex hardware by programming a personal computer.
      • Small size and low weight of equipment nowadays and the almost unlimited possibilities to travel to any place on earth, should appeal to the young adventurer.
      • Working at even higher frequencies is a challenge to the technically oriented amateur. Generating stable frequency at microwave frequencies can be very difficult. Commercial interest in these frequencies is usually broadband, whereas amateur radio mostly use narrow bandwidth systems.
      • New electronic components can be used in sensitive ultra high frequency transceivers, which can be used to bounce radio waves off natural obstructions, such as the moon (EME) or ionized layers in the atmosphere
      • Space communications, using amateur satellites, should appeal to the amateur with modest skills in communication practice and technology.
      • It may occur that an amateur payload is sent on an interplanetary mission. This will require the efforts of a great many amateurs. The constructing of a ground station is comparable with that of an EME station and many of these will have to work under remote control, in a manner comparable to that of a radio telescope. This poses a challenge for the computer programmer as well as for the amateur oriented on radio techniques.
      • The Internet opens up this new field for radio amateurs who enjoy using their multimedia computer. The added value to Amateur radio could be great.
      • Other functions of ham radio are: Distribution of general information, radio bulletins, articles
      • Training and education.
      • Publishing club activities.
      • Remote and ‘real-time’ operation of equipment for experimental purposes.

      Hints & Tips

      1. Here is a nifty way to waterproof coaxial connections. After connecting two coax cables with an UHF barrel adapter during a field day exercise, you should waterproof it against the inevitable overnight rain. To accomplish this in less than ten seconds, cut an eight inch length of 7/8th inch I.D. foam hot water pipe insulation (the non-split type), slide it over one coax connector, join the coaxes with a barrel, slide the insulation over the join and strap it TIGHTLY one inch from each end with nylon cable ties. Done.A five-foot length of pipe insulation costs $1.50 providing up to eight pieces. Nylon ties are $.05 each. That’s $.30 per connection. It’s cheaper than electrical tape and coax-seal and a lot faster. To disassemble, cut ties with diagonal pliers.waterproofcoax
      2. Most of us use our HT’s “barefoot”, that is with just a rubber ducky. We cannot be carrying around our larger HT antennas. As you know, rubber duckys fail miserably as a radiator due to their design … at most, they are just an extended dummy load acting as an antenna.It has been shown that the 2-meter “rubber ducky” antenna has -5db “negative gain” compared to a quarter-wave held at face level. In terms of effective radiated power (ERP), this means that a 5 watt HT with the rubber duck, radiates only 1 watt. Operating an HT on your belt results in another -20db attenuation, reducing ERP to 50 milliwatts! That’s 1/20 of 1 watt.Here is a hint that will help you modify your rubber ducky to make it more efficient … with just a piece of wire! So, get ready to use that piece of wire that you find in your junk box. Since you are using about “half” of your radiated power, you can add the other “half” by adding an external counterpoise, or “tiger” tail.So, let’s go! You can easily build that other “half” from a quarter-wave piece of stranded, insulated wire, crimped and soldered to a battery clip or use a small, spring tension clip that will fit the BNC antenna connector with the wire attached to it. Make sure that the connection is both a good mechanical and electrical connection.Always reinforce the soldered connection with heat shrink tubing or tape to resist flex and shorting to other components if possible.Now, when the counterpoise is clamped to the outer collar of the BNC connector on your HT antenna, it helps to prevent RF from coupling with your body, so your completed HT antenna “system” heading toward the ground, acts much like a center-fed dipole instead of an end-fed dummy load. So, there you have it — the missing “half” of your HT antenna.You also just built a directional antenna AND YOU DID NOT KNOW IT! In places where you have room, by extending the counterpoise HORIZONTALLY rather than hanging straight down, by moving your hand to steer the radiation pattern to where you need it. This produces a dramatically stronger signal than letting it “droop” toward the ground.Do some experimenting with the angle of the counterpoise to get the best results. You may be surprised.Use about 19.5 inches of wire for 2m; ll.5″ for 220; 6.5″ for 440. GOOD LUCK!
      3. If you are away from the 146.91 repeater and come upon an emergency, how would you handle the situation? A general guideline is this: If you are on an unfamiliar repeater and you have emergency traffic, say so! Example: “Can someone help me contact the Highway Patrol?” or “I need help contacting the Fire Department.” Asking “Is anybody monitoring?” May sound like an attempt to start a casual conversation. On many repeaters, you could be ignored. However, if you state that you have emergency traffic, people on many repeaters will drop what they are doing to help you. Note: If you are monitoring a repeater and someone asks for emergency assistance and you cannot help, BE SILENT! There are few things more stupid than someone breaking in to say they would like to help except that they forgot the codes, or that their home phone is busy so they can’t make the call for you.Recommendations:
        • If you have emergency traffic, say so immediately.
        • If you can help, please do.
        • If you cannot help, do not transmit.
      4. You may hear people using the term “73”, meaning best wishes. There is no “s” in the salutation “73”. (Other hams use “88” … no “s” … meaning “love and kisses”. This is typically between husbands and wives.) You will hear others saying “73s” and “88s” (wrong again!). You might even hear someone saying (yikes!) “threes and eights and all those good numbers!” Again WRONG!.
        Proper usage would be similar to this:

        • Voice: “OK, Sam, seventy-three and I will talk to you again.”
        • Voice: “73 for now.”
        • CW: “W9MZ de W9JR CUL 73 SK”
        • CW: “W9XXX de W9JR 73 88 SK”
      5. Using the term “For I.D.” is not necessary … in fact there is no FCC rule that say hams must use this term. There should be no reason to transmit your call sign other than to identify your station. Identification is required every 10 minutes during a conversation and at the end of the conversation or series of communications. Conversations need not come to a halt while you identify. Simply say your call sign once every ten minutes.

        • While talking, say your call sign once every 10 minutes. Don’t say “For I.D., this is KC9XXX”. Even worse, don’t say “For license preservation purposes, this is KC9XXX.”
        • If you hear someone say “For I.D.”, they may be trying to tell you that 10 minutes have passed and you should identify your station. Take the hint and say your call sign the next time it is your turn to talk.
      6. SAFETY FIRST. This is something we have to consider and be aware of when working with electronics. We get our share of high winds here in southwest Wisconsin. So, after a high wind, be sure and visually check your antennas frequently to make sure that they are not down. When transmitting, an antenna has a high current at the feed point and a HIGH VOLTAGE at the ends. That high voltage can be be enough to start a fire with the right amount of flammable material or gas surrounding it. Also if a human or pet can reach or touch the antenna when you are transmitting, one can get a very nasty RF burn. It doesn’t take much power. 100 watts can make you dance pretty fast when contacting an active antenna.
      7. Another tip. Using the phrase “clear and monitoring” is not really necessary. Neither term is required by the FCC or anybody else. If you can call another amateur, using his/her call sign and yours, and that person does not answer, it is not necessary to advise “clear”. You have already identified your station and any other identification is superfluous.

        • Use “clear” only to mean that you are shutting down operation and and will not be there to answer any subsequent calls. Under normal conditions, when you are finished with a contact but will continue to listen, it is sufficient (and right!) to merely say your call sign.
        • If you attempt to contact someone and there is no answer, you can notify others that you are finished by saying “KC9XXX clear” or “No contact, this is KC9xxx clear W9PVR repeater. This allows someone who may be been standing by to go ahead and make his/her call.
      8. Here’s a good hint we will have to remember for next Field Day. We use extension cord reels to keep our cords free of kinks, so why not use the same thing for our coax cable? These are handy for storing RG-8X and RG-8 coax cable. Makes rolling up cable after Field Day or other events a snap. This should help prevent kinks in the cable as you’re rolling the cable out. Hey, we could even use this idea in our own radio shacks!
      9. One of the most important things for new hams to learn is to “K-H-T.” That is “key, hesitate, talk.” You must consciously learn to push the microphone button, pause slightly, and then begin speaking. If you push the button and speak simultaneously, the first word or the first part of a word may be cut off. This does not facilitate effective communications. Hopefully, if you learn to do it correctly from the first day, it will become subconscious and you will do it automatically. If this is the case, you will earn the respect and admiration of your peers. If not, you will be forever labeled as a sub-standard operator.
      10. Have you ever been frustrated trying to get a nut or washer on a screw in a tight place? This is a good tip. While the screw may be easy to insert into a hole, the other side of the hole may be impossible to reach with fingers or pliers.You can put the nut or washer in place by first turning the overall object so that the screw is pointing “up.” Then slide the washer or nut, or both, on some solder (or copper wire). Pull the solder out far enough that you can get it to contact the top of the screw. Hold the washer and/or nut on the solder with your finger while you snake the solder down into the apparatus, to touch the end of the screw. Then let the nut/washer go: they will slide down the solder and onto the screw. This sketch demonstrates the idea:washerTurn the nut with another piece of solder or a long screwdriver until it starts onto the screw, then remove the solder. Continue working the nut onto the screw until it begins to snug up. Then finish tightening the screw with a standard screwdriver.


      Further information on amateur radio:

      Interesting publications in relation to Amateur radio:

      Interested in Scanning police frequencies?

      • If you are interested in monitoring public safety departments, here is a good site to get frequencies for your scanner. It was suggested by Chris, KC9CMD: Go here.
      • If you are interested in monitoring online police scanners, here is a good site to to listen to live public safety trafic. It was suggested by Chris, KC9CMD: Go here.