GB3CJ... 10M Repeater Northampton U.K.
[More information]


Height of Mounts Fire Station site Antenna
121 Metres Above Sea Level
Height of Receive Antenna on North Eastern side
128 Metres Above Sea Level
Access To Repeater
Input Frequency
29.540 MHz
Output Frequency
29.640 MHz
Repeater Keeper
Dave (G4SCJ) E-mail Dave


The following is a set of recommendations for obtaining the best performance when accessing the 10M repeater GB3CJ.

In order to access the repeater s frequency modulated carrier with a sub-audible tone of 77Hz is required on the input frequency of 29.540 MHz

Particular attention must be paid to the transmitting stations' deviation settings.

The optimum deviation is ± 3KHz and the absolute maximum is ± 5KHz. Above this, severe clipping of the audio occurs causing distortion.

The optimum deviation for the 77Hz sub-audible tone is ± 500Hz and the absolute maximum is ± 600Hz before distortion is caused to the audio modulation.

It is advisable to check your equipment deviation using a calibrated modulation meter. If you are unsure then your local radio club or repeater group should be able to provide assistance.