GB3WC 23cm FM voice repeater (RM15)
Repeater Tx 1297.375Mhz (RM15), Rx 1291.375Mhz,
shift -6Mhz. RF output 25watts erp from a colinear 10m agl.
Access is via a CTCSS tone of 82.5Hz (D) or a tone burst of 1750hz. The repeater sends the ID 'GB3WC D' in CW every 15 minutes without CTCSS.
The transmitter consists of a Kenwood TM531e running 1W via a 6db pad to a Mitsubishi brick type amplifier which produces 18W output into the cavity filters.
The receiver is another TM531e which replaces a crystal controlled Camtech 23cm receiver sold by cirkit in the early nineties and first published in 'Ham Radio Today' in March 1987. This has improved the sensitivity and also eliminated the de-sense we were experiencing with the camtech receiver.
All the interfacing with the NHRC3+ logic housed in the diecast box in the middle is via the microphone socket of each transceiver. CTCSS encode and decode is provided by the excellent TS-64ds supplied by Jescom, Inc.
Here are some ideas for making a simple double quad antenna for repeater access, DL5NEG, PE1RKI.