GB3NR

Location Norwich
gb3nrThe Norwich UHF repeater, GB3NR, RB0, 433.000 MHz/434.600MHz was first operational on TBC from the shack of the Norfolk Amateur Radio Club The Norwich Repeater Group was started by, G8GTZ,G8JWT & G4AUV.
Much has happened since then and NR has moved, although only once so far. Its current location provides better coverage than the original site

Accomodation
NR’s shack was was beautifully crafted from a quantity of carbon based material by G8PRI. After a period of 20 or so years it has not turned into diamonds. Maintenance required soon (2002), materials already sourced.
Technical
Antenna PROCOM CXL70-5
Feeder Andrew LDF4-50
Transmitter Philips T412
PA removed and substituted for BFR96 driving MHW 710 in a spare T412 box, 13 Watts output and continuously rated.CTCSS installed, 94.8 Hz, only active during talkthough.
Pye412Receiver PhilipsF496, only using RX board in
diecast box and then rack mounted. CTCSS decode installed, 94.8 Hz, only used for access in parallel with 1750 Hz.
The filtering in this receiver is for 12.5 KHz Channel Spacing.
Duplexer Homemade The design is a modification of that by W1GAN, Link to W3KKC’s Website¬† easy to make, non adjustable inner, capacitivly loaded, excellent performance.Thanks to the originator of this modified design, who also donated the original two cavities. An additional band pass filter is fitted in the RX path and an isolator at the transmitter output.
Controller Homemade Heavily modified GB3US Mk1.

Donations to G4LUA (QTHR)
The Group wish to thank all those who contributed designs components,materials and time,
The Repeater Management Comittee, The Microwave beacon co-ordinator, And Norwich City Council.

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