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What is HAM Radio?

We must say even now that HAM Radio has nothing to do with "ham". It is not eatable, but it is a very interesting means how to spend your leasure time, that people have been enjoying for more then one hundred years. It is Amateur Radio.

Likewise the necessity of fast access to information helped to develop the Internet, similarly, our great-grandfathers were obsessed by a thought not only listen to the radio but also to transmit. Quite a new hobby has risen: Amateur Radio, also called HAM Radio, and those who were keen on it, were called radio amateurs.

How it all began...

In 1995, one hundred years passed since the Italian experimentator Guglielmo Marconi found a practical use of previous theoretic works of Mr.Maxwell and Mr.Hertz about electromagnetic waves, and the world could recognise a phenomenon which we briefly name "radio". Without thinking about it, radio is now intimately joined to our lives, beginning with reception of the radio and television and ending with pocket radio telephones.


At that pioneer days everything was simple. The so called "spark telegraphy" was used.

Schematic Diagramm

The source of oscillation was a permanent electric discharge in the spark gap,

Spark Gap

connected to the inductor, still being a means of fun at scholls in physics lessons.


Reception of the signal was realised by a means of glass tube filled with iron swarf - so called coherer. The coherer through relay



directed the standard Morse telegraph printer.

Morse Telegraph

The necessary parts could be found in every better equipped school cabinet or sometimes in a rubbish heap. One of the first known radio amateur stations was built in the USA by Hiram Percy Maxim, W1AW, sometime in 1910. He utilised parts from a broken Ford T car which he bought for about $50...

The period pictures were taken from the book „Electrotechnik fuer Jungen", a nice German translation of „Harper´s Elektricity Book for Boys" from the year 1907. 

Amateur radio experienced the great boom after the First World War, when the broadcasting was spread in Europe, too. The radio amateurs significantly contributed to practical utilisation of the whole spectrum of radio waves. The professionals broadcasted on long or medium waves, the short waves were considered to be valueless and nothing was known about very short waves. When Marconi interconnected the Europe and America by radio for the first time, he needed a lot of kilowatts of output on long waves and many kilometres of aerials. In 1923 the radio amateurs found that for the same purpose on short waves, they need energy of one bulb and only several metres of wire as an aerial.

Transatlantic experiments were also tempting for the first known Czech radio amateur Pravoslav Motycka, OK1AB. He worked in the Prague state and business Palace Lucerna, whose owner Vaclav Havel, the grandfather of ex-president of CR, was a favourer of modern technique and a member of the former Czechoslovak Radio Club (focused on development of the radio broadcasting). He understood Motycka´s experiments and so the operators room of the cinema in Lucerna Palace became a scene of the first amateur radio experiments in our country. At the end of 1924 Motycka established the first amateur radio contact in Czechoslovakia. He had a lot of friends and followers and at the end of thirties there were several hundreds of radio amateurs in Czechoslovakia.


LUCERNA Palace on the period photo
of practically invisible Motycka's aerial

Soon the radio amateur activity turned up to be not only a hobby. All the world understood it when in 1928 a Russian radio amateur was the first who received a signal from the airship ITALIA which had wrecked on the way from the North Pole (there was also a Czech scientist Dr. Behounek on board). The preparedness of radio amateurs to offer a quick contact helped a lot at natural disasters and other accidents. In tropical areas the radio amateurs are often the last help when everything stops working at hurricanes and storms; in developed countries they are often the first people who appear with their stations at traffic accidents.

HAM Radio Today

In the field of hobbies, the radio definitelly stopped being an exclusive domain of radio amateurs. Also various other hobbyists, short wave radio and TV DX listeners, as well as the Citizen´s Band users and many others work with it. But amateur radio is still alive and has more than one million favourers all over the world. One of the main reasons for the popularity of amateur radio is, that it keeps the step with all the news which appear in the radio telecommunication technique.

From the beginning, operation on short waves is the base of the radio amateur activity. It enables contacts with all the world including exotic countries, about which we can only dream. In a lot of world places the amateurs are active only sometimes, or never, mainly for geographical or political reasons (during totalitarian regime Albany was the worst accessible country). Just the contact with so rarity places is the aim of activity, called DXing.

The radio amateurs exchange confirmation about established contacts among themselves, the so-called QSL cards. It is a big dream of every amateur to have cards from all the world countries, but practically, the dream cannot be satisfied because during a person´s life it never hapens, that in every country would be active some radio amateur. But at least the competitors try to achieve the most. It can fulfil all the person´s lifelong leasure time.

Radio amateur clubs issue sport trophies - radio amateur awards for their fans. Thousands of various awards are issued, and each has a specific rules. Sometimes it is a contact with most of the countries in the world, sometimes a contact with amateur stations of a certain country or region; otherwhile it is necessary to fulfil some other criteria in a specific time. One of the possible aims of the radio amateurs is a big collection of these awards. Again: it is not in a person´s strength to collect them all, so there is always something to seek for.

All we know from our experience with television and FM radio reception on very high frequencies (frequencies above 30 MHz), that the good reception is possible only from near transmitters, distant not more than some dozens of kilometres. The aim of the radio amateurs, working with the high frequencies, is to vanquish these limits and overtake long distances. They utilise not only a clever technology but also good knowledge of factors that positively influence propagation of very short waves. Among these factors belong, for example: boundaries between hot and cold air masses, the so-called sporadic E-layer, aurora, or strong ionisation of air which sometimes originates on the orbit of meteor penetrating the Earth atmosphere. The professionals cannot rely on these appearances, but amateurs can establish a contact that reaches hundreds or thousands of kilometres with their help.

When nature cannot help, we use technique. The radio amateurs utilise the so-called repeaters which they built on many hills and high buildings. The repeater is a collaterally working receiver and transmitter; it receives the signal on one frequency and transmitts it immediately on the other frequency. Because it is placed high above the terrain, a large area is covered by the signal and it helps the users to get through to longer distances (the radiotelephone systems work in the same way). Most of the amateurs have a pocket radio stations (handie-talkies) which they use when driving or walking. They are only organisation aids or fancy means because from the sportive viewpoint, the contacts via ground repeaters are valueless. Sometimes, the lovers of high frequency appliances launch the repeaters on the balloons into the high atmosphere levels, where the reach of contact is higher.

But it is not the end of magic. Since 1960, a lot of amateur radio satellites have been orbiting the Earth. They are even higher than the balloons so the signal can cover quite a large area of the Earth - usually a circle about 4000 km in diameter. The TV satellites, as PanAmSat or ASTRA, use the same principle. Unlike the geostationary television satellites, the amateur satellites circulate around the Earth, most often on the low orbit. Thanks to it they are not above the horizon for a long time but their signal gradually covers all settled areas, and the same satellite can be utilised by all the radio amateurs in the world. On the amateur satellites demonstrate the principles of cosmic communication also technical universities.

It is interesting, that radio amateurs are often a part of a crew in American rocket planes and Russian orbiting complex MIR. They transmit spoken words or use the so-called „packet-radio". Other way of amateur radio exploration of Cosmos is establishment of a contact through reverberation of radio waves from the surface of the Moon (Moon bounce). It is not any easy. The Moon is very far and the signal must get over the route twice. It will also lose intensity due to absorption in the Moon surface. Therefore, such contacts ask for the best and most effective technique with skilled operator, a master-work.

Although it is hard to imagine, contests are held on the field of amateur radio. The aims are different: for example to get contacts with most other amateur stations in most of the countries during given time. Or, in some other contests you get points for every kilometre of distance being overtaken by the signal of the competitor´s station. There is a contest almost every weekend. In some contests it is useful to install the radiostation in an elevated place, preferably in the mountains. The operation in improvised conditions is better in a group of similar devotees, you can also utilise the help of other allied souls, so the contests bring not only a radio amateur experience but also a lot of fun with friends in a cosy cottage in the nice mountain scenery.

The first kind of instrument, used for communication in radio (and amateur radio as well), were telegraph signals - Morse code. Amateurs have been using code until today, because it has a lot of advantages. The main contribution of the Morse code is its great penetration force, due to which it is possible to overtake great distance with use of only small power. The Morse code also pulls down the language barriers, because it uses a system of internationally adopted abbreviations for the communication, where, for example, the abbreviation HAM indicates a radio amateur. The radio amateurs also use spoken words. For the speech transmission they use SSB, modern type of amplitude modulation, and also narrow-band frequency modulation on high frequencies.

The Morse code is one of methods of coding of human speech. Today, much more advanced systems are used (also by radio amateurs). The radio amateurs utilise radioteletype (RTTY) and similar systems (AMTOR, PACTOR, CLOVER and others, which are mostly amateur modifications of professional systems). The most popular of them is packet radio, which is a radio amateur kind of Internet. It provides a transmission of digital information by a means of the modification of protocol X.25. The network of the packet radio covers the whole world, and also BBS (databanks for storage and exchange of information) and electronic mail are its constituent parts. You do not need send e-mail to a friend to Australia only through Internet, but also through amateur packet radio, and if you have nothing better to do, you can spend a lot of hours by investigation of news and interesting programs in dozens of BBS in the whole Europe.

The amateurs can also transmit picture signals. A long tradition has the so-called Slow Scan TV (SSTV) which was used to transmit pictures from the first landing attempts of American astronauts on the Moon. Today, people make experiments with various digital systems and on UHF frequencies it is possible to use a classic television norm.

When the radio amateur is tired by sitting at the transmitter, he can devote himself to activities of a sport character. The most known is Amateur Radio Direction Finding - ARDF, so-called „fox hunting". The purpose of the game is to find hidden transmitters with help of direction-finding receivers as quickly as possible. It is a sport discipline in which the world championships are held. Another sport discipline (also being performed on the world championships) is indoor sport telegraphy, where the competitors must transmit and receive simulated radiograms as quickly and correctly as possible. All these kinds of sport are very attractive and a lot of people who are not interested in other radio amateur activities are very keen on it.

Difference Between CB and HAM Radio

A lot of people think that amateur radio and usage of Citizen´s Bands - CB - are almost the same. But there are considerable differencies. Even if radio waves are common instrument, the basic difference is in function and content of both the hobbies.

As it is evident from the name, the Citizen´s Bands are devoted for wider usage: for people´s talking about any topic. We can hear private conversation, job coordination of taxi drivers, but most of all only familiar talking to overtake boredom. If people do not have any concrete utilisation of the CB, they will get tired of it very quickly. All the same people and things forever ... . CB has universal usage and its advantage is the easy accessability. But it also disadvantages: narrow frequency band and small output power, and therefore only small reach of several dozens of kilometres. People spend on the station and aerial only a little ammount of money and they do not need any licence or qualification exams for the operation.

Radio amateurs have harder job, but the reward is sweeter. If they want to start, they have to ask PTT office in their country for the licence, and it is conditioned by passing exams. If they want to communicate with all the world on SW bands, they have to learn Morse code. The content of the contacts is restricted by international rules to affairs, concerning a radio amateur activity and to unimportant notes which should not be sent by mail. The post offices were afraid of being deprived of profits by the radio amateurs (and they knew why). The commerce broadcasting is strictly forbidden.

In spite of several restrictions, amateur radio has a lot of positive factors. Instead of several watts, radio amateurs can use power of hundreds of watts which allows them to communicate with the whole world. Instead of a few VHF frequencies, they can utilise a continuous range of frequencies from short waves to the highest UHF frequencies which still cannot be regularly utilised by today's technical means. In the domain of short waves there are 9 bands which allow to utilise all possibilities of physical conditions of radio waves spreading. And there are a lot of various types of modulation and communication protocols, too. The CB users can only dream about all of it.

The main attraction of the amateur radio is the fact that it has a content and a lot of aims: new countries all the time, new awards, better position in contests, experiments with a lot of technical news. It is such a wide hobby that it is not possible to master everything.

I Am Interested in the HAM Radio - What Shall I Do?

Before you start, it is necessary to get acquainted with the amateur radio and find out if it is what you are exactly interested in.

For listening short waves, you need a radio for 3,5 -3,8 MHz (which you can listen mainly from evening to morning), or 7,0 - 7,1 MHz (where the radio amateurs are heard during all the day) and 14,0 - 14,35 MHz (not at night). The radio must have a beating frequency oscillator (BFO) so that you could hear signals of telegraphy and SSB. You can listen to the short waves broadcasting by every better radio, but only the most expensive radios have BFO. At the beginning you can borrow it from your friend, or you can buy a surplus military radio in a bazaar with military articles.

A radio set, able to receive narrow-band frequency modulation on 145-146 MHz is necessary for listening of VHF. Here, in the range of 145,6 - 145,8 MHz, you can find output channels of repeaters. Normal consumer radio does not work in this band. You can borrow the so-called scanner, a favourite general coverage receiver which can listen to various services in a wide spectre: ambulances, firemen, taxis, and so on, and is quite cheap. In case of a surplus radio station - military or other - you would have to re-tune it to an amateur band which is a job for an experienced technician with good equipment.

You can listen to the radio amateur bands for a longer time. This kind of listening, called Short Wave Listening - SWL is a particular amateur radio activity. For listenings it is possible to get QLS cards, which are the base for getting a lot of various awards issued especially to listeners. SW listening is also a superb preparation for your own transmitting.

If you are experienced in practical radio, you can build the direct conversion receiver. There are many directions how to do it in radio amateur magazines and other literature.

It is also good for you to read something about amateur radio so that you could better understand what you hear. There are a lot of suitable handbooks offered by radio amateur organisations.

The real magic world will be open for everybody who learns Morse code. It is not enough to know it in the form of dits and dashes or with help of auxiliary words. The transmitting in practice is very quick and you do not have time enough to draw all the dits and dashes you hear. In the moment you hear the rhythm of the code, you must associate it immediately with single letters and then complete words in your mind. It requires practice, but fortunately neither long nor difficult. In many archives on Internet you can find helpful training programmes. If you practice the alphabet 20-30 minutes daily, you will understand slower tranmitting very soon, and then it is enough to follow the practical operation regularly. The shape of the figures will be fixed in your mind more quickly, if you not only listen to the code, but also transmit it. For that, you must buy telegraph key and earphones, and according to the HAM Radio magazines, you have to build a tone oscillator.

You can accelerate all these steps, if you make friends with a radio amateur or find any radio club. There, you will obtain help and practical advice which cannot be replaced by any book. If there are conditions for that in the club, and if it is permitted by the law of your country, you can start transmitting in the club under the supervision of more experienced people. The practice in the club usually means a good preparation for you own future activity and for exams, you have to pass to get your own licence.

After you have learnt something and you are sure to find the right hobby for you, it is time to get prepared for exams. Publications issued by the radio amateur clubs are quite useful. You do not have to be afraid of the exams, because the members of the examination board are usually the radio amateurs, who will ask you only important questions necessary for practice, and the atmosphere is always friendly and collegiate. If you do not pass the exams for the first time, it is possible to repeat them.

You passed the exams and got your own licence. Then you can start building your own amateur station. The important thing is a quality of the transmitted signal. You do not have to obstruct overcrowded amateur bands, nor transmit undesirable signals out of the amateur bands. You also do not have to disturb any important services, radio, TV or other consumer technique, otherwise your neighbours will be the first to beat you.

Now you are facing the question what to buy and how much it will cost. There are solutions for every pocket. If you have a look, how much young people spend for example on a ski outfit, computer, mountain bicycle, entertainment electronics, or other things, you will see that your hobby will cost you approximately the same (if you will not buy only new things) money which you can earn in some season works and "with a little help" of your parrents.

For your first attempt with low power, you can build a direct conversion transceiver (which is a combination of a receiver and transmitter) according to a schematic diagramms in magazines. It will cost only a little. This kind of transmiting with low power is a particular radio amateur activity, known as QRP. Sometimes it is hard to believe how large distance it is possible to get over with power, similar to a pocket battery lamp. But soon, especially the young amateur will be bored waiting in a queue even for closer stations and will be looking for more powerful equipment. Then it is necessary to pay more.

Everybody, who must save money, can visit shops with surplus military gear. Some appliances (though with electron tubes and very heavy) are very good and you get an effective short wave station very cheap, but you will have a separate receiver and a separate transmitter which will occupy a lot of space.

It is better to buy a second-hand equipment that was made directly for amateurs. You can do your shopping in amateur flea markets where it is possible to bargain the price, but there are not good conditions for testing of the equipment.

The best thing is not to save money and buy a new apparatus.

It is always better to consult your decisions with an experienced radio amateur before you buy something. You will unconditionally need help, if you buy something second-hand.

Where to Look for Help?

The radio amateurs of all the world associate themselves into clubs or societies, which help them solve common problems, offer various services, and are able to help the beginners. There are similar clubs in most countries of the world. You can find important contacts on WWW pages of the International Amateur Radio Union.

A Word for Conclusion

Finally, there is an answer for the question: what does the word HAM mean?

In 1908 in the USA, the gentlemen Hyman, Almy and Murray started to operate the amateur station of Harvard Radio Club. At that time, the amateurs did not use international call signs, so they reported themselves on the air by association of their names (similarly, it happens on CB today). It was too long, and so in 1910 they reduced it only to the initials: HAM.

In 1911 Hayman appeared in the USA Congress and asked for more gracious approach of American legislation to radio amateurs. The word HAM was used in the debate as a concrete example by all the speaking congressmen, and it became a common word for amateur radio station.

According to the Florida Skip Magazine - 1959, taken from WWW pages of The Whiterook Products Company.

© OK1XU, 1997