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The GB3KT Archive Page

      GB3KT Goes 'Off air'

      Sadly, due to lack of support, the Kent Television Group ATV repeater, GB3KT, had to be taken off the air on Easter Monday 25th. April 2011. The repeater had been located on the Isle of Sheppey in Kent for the past fourteen years, having started full operational service in May 1997. The repeater was the prime purpose of the Kent Television Group (KTG) which had been formally set up in August 1990, after an initial gathering of interested parties in July of that year. At one point the KTG boasted a membership of 47, the years have seen this drop to a current membership of 6 and an inability to form a working Committee. Prior to coming into full service, the GB3KT equipment was tested on a manned basis at the QTHs of G4AYT, G4JMP and G4CZJ.


Some of the Original Testcards and Captions used at GB3KT (From KTG Website courtesy of Webmaster G6PKS)


                    Mast Top to East                               Mast Top to South East                            Mast Top to South                                    View to West

Views from GB3KT's Old Site (Mast Top Photos: G8GHH)

      GB3KT Equipment

      GB3KT was first built into a small rack just 9U high (picture opposite, top right). The transmitter tray contains a Solent 1W PLL driver running into a 20W PA brick kindly donated by Icom (UK) Ltd. Testcards and captions are generated by a Cropready TCG, the original version had a 'GB3KT Ready' caption instead of the current 'P' meter when an incoming signal drops.

      A larger rack was eventually required (donated by G8NAV) when test equipment was added (picture opposite, bottom right) and other additions were made. The system has a DTMF decoder with control facilities and the option of turning on or off a 1kHz audio tone. There is also the option by using a CTCSS tone on the incoming signal to display the 'P' meter while the tone is present, allowing stations with look through or by talkback to adjust beam headings accurately. The logic consists of the BATC Teletron and Z80 processor. The RX has a GasFet pre-amp and modified tuner/6MHz sound detector.

      A back up power supply was also added to the system by Technical Co-ordinator G8GHH as it was soon discovered that mains power outages at the site were quite common.

      GB3KT's antenna is a double Alford Slot made by JVL. The original version was not made as requested and had to be replaced and eventually a third was purchased. One of the latter two suffered severe damage during high winds on the Isle of Sheppey. Reception (1249MHz) is on the top slot and transmission (1310MHz) on the lower.

      At the time of writing the equipment has been thoroughly cleaned and is being stored at the QTH of Brian, G6PKS, in Herne Bay (apart from the back up PSU). The system will get an occasional 'airing' during KTG activity nights, on a manned basis, using the callsign G6PKS.


                      Broken Antenna                                  Replaced with Spare                  Rigger G8GHH (Photo: G6PKS)             G4AYT RX on site Checking

      KTG Members and GB3KT (Mostly off screen, in no particular order)





      Can you put a name and callsign (where applicable) to these faces? To help you, there's a clue with the first one and a bit of one with the second! Answers can be found HERE

      It is with regret and great sadness that I have to report five of the above are known to be deceased.

      Do you have any photos that could be added to this archive?

      GB3KT DX Reception

      DX reception reports for GB3KT have been a bit 'thin on the ground', one P3 report was received from F6ANO located 40km ESE of Paris in September 2010 and several reports have been received from Belgium and Holland over the years. On a German website there is a section entitled 'ATV DX News from Juergen, DJ7RI, in Kiel, northern Germany' in which it says "On our western coast GB3KT is received quite regularly" (Translation thanks to Klaus, DL4KCK).

      Reports from within the UK have been received, but no record has been kept of these. Nick, G4IMO, Wisbech, has seen GB3KT at P3. If you are aware of any other such reports from beyond the 'normal' service area, please e-mail G4AYT the details.

      GB3KT Video

      A very short video (just over 3 minutes) has been posted on youtube by Gary, G4GHD (info from Steve, G4HTZ - thanks). The video appears to have been recorded 'off air' and shows a transmission on GB3KT of a recording by G4AYT made when the repeater first went on air. View video HERE