The repeater is located near Fakenham.
Technical Information:-
RX : Wood & Douglas unit was used up to 2000 when it was replaced with a Comtech front end + bespoke De-emphasis etc. with better sensitivity.
TX : Wood & Douglas PLL exciter + Mitsubishi PA run at 12W & a 3 pole interdigital filter. Power supply : Linear 10A 13.5v with 4 x 3055 pass transistors – ancient but reliable technology!
Logic : bespoke – based on Cropredy test card generator modified in 1991 to produce a live analogue type S meter to show Rx signal level. In 2000 a PC was added to display pictures & info. A wireless access point was added in 2008 for remote update .
A live stream  is available here
Antennas: 2 x Alford slot aerials (1 TX & 1 RX – default rx antenna) & 4 Directional DTMF selectable sectors (swiss quads “) added in 1992 when the tower was replaced. Structures : 10metre mast initially used was replaced in 1992 with a Francis & Lewis 22m TT30 commercial tower.
Freq Output 1316Mhz
Freq Input 1249Mhz with 1sec Video

 Live Streams
Streams for GB3TN and GB3NV are available from BATC



2013 Update
GB3TN has been updated recently thanks to Mark G4WVU with an DVB-s Digital input on 70cm. 437Mhz and a wheel antenna on top of the tower.
Also courtesy of Mark G0LGJ a video stream is running giving video and audio from GB3TN output, stream runs from 07:00 – 01:00
Feedback to Mark G4WVU or Mark G0LGJ

2021 Update
New 70cm RX Sector antennas

GB3TN Block Diagram
Click to open PDF


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