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| AMATEUR TELEVISION |
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| Of the wavebands allocated to Irish Radio Experimenters for the transmission of Television signals, the most popular are the 23 centimetre and the 3 centimetre bands. |
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| The 23 cm band has similar characteristics to normal UHF domestic TV. That is, similar antennas are used (Yagis of the appropriate dimensions) and signals can usually be well received up to distances of 60 or 70 miles. In exceptional meteorological conditions, the range can extend to 170-200 miles. That is like Dublin to Manchester. Ranges can also be increased by the use of ATV Repeaters . |
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| Most activity however, is made up of local 'nets' where 3, 4 or 5 experimenters may take it in turns to send each other live pictures with accompanying sound, when they may be showing their latest pieces of equipment, discussing and solving each others problems, or just having a friendly chat. Many contacts take on the atmosphere of a Radio Club meeting but from the comfort of your own radio room. |
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| The 3cm band has the characteristics of satellite TV. Signals are normally line-of-sight, and wll not go through buildings or hills. |
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| For antennas we use Satellite dishes which must be more accurately aimed at the other station than is the case on 23 centimetres. |
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| Equipment for transmitting on either band is usually constructed from kits of parts marketed by specialist suppliers. Receivers are commonly made up by modifying obsolete Satellite receivers, many of which lend themselves admirably for this job. |
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| The Sat' receiver already covers 23cm's, and with a suitable LNB will cover 3cm's. |
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| The popular way to provide video signals for your station is to use a camcorder, which provides live pictures with accompanying sound and also prerecorded material on it's internal video recorder. Most stations add a VHS video recorder, and maybe a computer Test Card and Caption Generator, software for which is very cheap. |
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| Some operators have made up portable outside broadcasting units for field day activity and for contacting stations not reached from the home qth. |
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