As a child I was fascinated by the magic that electricity is. One of my pals and myself experimented with batteries and lights and electromagnets. We made up a crystal set from a diode that we somehow got. I can't remember where. We tried, unsuccessfully, to make one from an actual crystal and 'cats whisker' but failed. Such diodes are, I think, called end source diodes. In fact the diode-based crystal set did not work where we lived in West Co. Waterford as we were out of range of any transmitter. It was not until one or the other of us visited Dublin that we got it to work and so prove that our experiments were successful. This was my introduction to radio and I am still interested in radio both as a listener of broadcast programmes and as a radio amateur. Many years ago I passed the examination in theory and got a license from the ODTR to transmit as an Amateur Radio Experimenter. The ODTR is the organisation set up by the Department of Communications to control the airwaves. The ODTR has recently been 're-branded' as ComReg. The mind boggles! My call sign is EI6EVB and I am a member of The Cork Radio Club whose callsign is EI5CRC. I am also a member of The Irish Radio Transmitters Society. This is the 'umbrella' organisation that most radio clubs are affiliated to. Check the 'highlights' for links to the relevant sites.

Most Radio Amateurs will be familiar with Slow Scan Television. I have never seen this but it is not 'television' as is generally accepted in the domestic situation. The frequencies used are the High Frequencies and the picture quality is generally not of a commercial quality. While saying this it must be remembered that the pictures are transmitted, with very little power, over thousands of miles in some instances. On top of all this the pictures are not 'moving pictures' as we have become familiar with. The pictures transmitted are a series of stills (isn't that what movie film is, I hear you say) but the interval between the stills can be a number of seconds. This is not too unlike what we get from web cams on the Internet. It is because of this 'slow' refreshment of pictures or scans that the 'slow scan television' gets its name.

Cork Radio Club have a wealth of expertise among its members, few more expert than, Aedan EI 3 EG, who has been experimenting with and set up a television repeater operating on the Amateur Bands. This is 'real' television in full colour with stereo sound and of a quality comparable, if not better than locally available commercial television. He has written a very interesting article on what was involved in this. Click on the link from his name above and read the article.

When I mention to non Amateur Radio people that the Radio Club has a 'television station' they do show interest but their next question is 'what sort of programmes do you transmit!' Well, first of all our objective is not to offer a competing service to any of the locally available television channels. The purpose of this television transmitter is for our own experimental purposes and to show what can be done on home made equipment and circuitry designed or modified by Aedan and friends. What is transmitted is a four 'window' in one screen picture initially. One 'window', to use the computer term, shows our test card and station announcements with our call sign; another 'window' shows a slide show of Club members engaged in various activities, social and experimental, it also shows some circuit diagrams of recently constructed projects such as a 'logic probe', designed by the late Fred EI 2 EG; a third 'window' has a view from a video camera mounted on the transmitting mast, this shows the flight path to Runway 17 at Cork Airport and planes can be seen making their approach, day and night; the fourth 'window' is available for 'input' from Amateurs who have transmitting equipment. This is less used but on Club nights some members transmit from their 'Shacks' and we can see and speak to them as they operate their radio equipment. On other nights a video of radio related interest would be transmitted for an hour or so. You may very well think that such a four in one screen makes viewing of one of the screens a bit tiresome. That has been thought of too, if you wish to 'fill' the screen with just one of the pictures it is possible to transmit a DTMF tone to the 'repeater' and select the screen you want, this will then be shown full size until you wish to switch to another or to go back to the four window screen. Rather technical but ingenious.

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