GB3XG BRISTOL'S 10GHz Amateur TV Repeater

GB3XG the groups 10Ghz repeater uses a very advanced logic control system based on a Motorola 8 bit “6809” micro. This was developed by John Hudson G3RFL. The system has all the bells and whistles that most users seem to expect these days, these being DTMF control, numerous testcards. Since the recent change in frequency imposed by the Department of trade and industry (DTI) it has taken a lot of hard work to get the system up and running again.

The following people must be thanked for all the hours of hard work that they have put in over many months.John G3RFL (Logic hardware & Software), Ivor G1IXF (Site Mechanical engineering works), Ross G0WJR (Expensive test equipment facilities), Ian G6TVJ (Adivce on all video matters) Tests have been conducted recently and the coverage over to Wales appears to be particularly excellent, this has in turn encouraged lots more interest in that part of the country.

To receive pictures from GB3XG is reasonably simple all you need is a satellite RX and a modified Low noise block converter or LNB for short. This is a device that takes the 10GHZ band and shifts it down in to an IF which is then processed in the normal way by the receiver. Converted LNB's are readily available from Bob Platts G8OZP who advertises in CQ-TV.

Above close up detail of the Alford slot antenna used at GB3XG.

The screen below is one of the testcard sequences that may be seen whilst the repeater is in beacon mode awaiting an input signal.