GB3NB

Location :-
gb3nb Location :- The repeater is located at Stoke Holy Cross in  Norfolk.
Technical information :- The Repeater consists of 1 Jaybeam 1/2 wave dipole Type 7050 cut for 145 Mhz. The antenna height is approx. 60M, this is fed with 80M of Andrew LDF-450 heliax giving approx. 3db signal loss. The duplexer consists of 6 cavities constructed to a John BilodeauWigan design originally published in July 72 QST also in “FM & REPEATERS “ and recently reprinted in ARRL antenna handbook 18th edition.
Tx Energy is fed into the duplexer via a circulator and port 3 is terminated in a 50ohm dummy load ensuring a good match at all times thereby reducing any spurious emissions being made.
The TX/RX consists of a Pye/Phillips units (T4002 & R4002), logic is a modified GB3US mk1 with external pip tone generation at 875Hz & 1750Hz tone generation by a 7.168Mhz Xtal.
CTCSS is also implemented on 94.8hz (F) There is no Timeout . A 1750hz tone or CTCSS will need to be used to re access the repeater. Output power is 25 W ERP.
GB3NB Keeper is G8VLL

GB3NB is used for various nets, Norfolk Amateur Radio Club net on a Monday evening, Echolink net on a Tuesday evening  and the RGSB News on a Sunday evening.

Leave a Reply