Radio wasn’t made first as an advanced broadcasting station but it was made like a little amateur station. There were people who were operating transmitters and sending signals "on air" but those operators wouldn’t have any meaning if there wouldn’t be a wide audience of listeners.
Listening to radio became a hobby probably from the first days of existence of the radio itself. There were always radio stations broadcasting signals and there were always people who listened to these broadcasts from their homes, work places, rest places, in noisy factories and quite offices. Very often people listened to radio for the sake of listening, not even going deeply into the information they received. That made a difference in types of radio listeners.
Today radio listeners can be divided in several groups dependent on the type of radio signals they receive and process, but in general radio listening can be either hobby or profession. In this article I want to talk about listening radio as a hobby and here are a few different types of signals that received and processed by those people. Major groups are divided by length of radio waves and by received modulation of radio signal, and here we have
* Broadcasting stations listeners on long waves, middle waves, short waves, and ultra high frequencies;
* Special stations listeners who listen to the signals from space stations, sattelites, boats, emergency stations etc.;
* Various Amateur radio listeners who are listening to the conversations of amateur radio operators on assigned HAM radio bands. Here I can also mention listeners of amateur TV stations as well as amateur Ultra High Frequency stations
This topic is very large and describing every aspect of this hobby and every type of listeners would take quite some time. I will talk here about Short Wave Listeners (SWL) who are listening amateur radio bands.
In old times most of the world radio licensing institutions were issuing special listening identification numbers (call signs) and those call signs were looking quite different from the operational calls, however, they contain the same parts: prefix, number and suffix (very often listener’s calls don’t have suffix and/or have special prefix) In general prefix contains information about location of the station (in operational calls part of the suffix and number can serve the same purpose), number in SWL call is the mane identification of certain listener, it is unique for the issuing institution. The suffix in SWL call can be avoid or sometimes bears the identification of issuer organization/club. For example I can show you my own SWL call – SM6011SWL SM6 – is a prefix meaning that I’m located in western part of Sweden, 011 – is a unique identifier, SWL – suffix means I’m part of SWL radio club.
In present time many of the licensing institutions dropped the issuing of the listeners IDs and simplified issuing of operational call signs. This allowed many international organizations to start issuing listeners IDs. Many HAM radio operators still want to have listener’s calls for cases when they hear interesting rare station but this station doesn’t hear them. Then operator becomes listener, and goes to the next part of this hobby described belove:
Well you may ask why cant I simply listen radio without any ID? Of course you can listen without ID but listening is only one part of SWL hobby, the other large interest is to exchange cards, proving the fact of the heard station being on air at the time of reception. This cards are usually contain information about date, time, bands, quality of signal of heard station and call sign of the operator with with call of operator that he/she had a contact with. These cards are usually beautifully made and worth as collectible items. To send the card you need to identify yourself as uniquely as possible and call sign is a great tool for identification, the person involved in this hobby can tell a lot about other person just by his/her call.
What do you need to start listening? Of course you need a special receiver.
* Nice to have specially made for shortwave “communicational receiver” but those cost quite some money. You can go for some cheaper portable receivers that have ability to receive SSB(Single Side Band) modulated signals, which are used by amateur radio stations.
* Also, you would need to design and create your card that you will exchange with heard operators, unless you don’t want to do it, then you don’t need call sign either.
* If you decided to go for card collection as well, then you need to apply for your listener’s call sign which can be issued either by local radio club or one of international clubs.
Now, to get more information about this hobby and some more specifics (like frequencies of amateur radio) you can search internet for “SWL” or “HAM radio”. Hope you would be interested in this hobby and it will bring you a lot of joy.