Here’s the 5th video [2 parts ‘A’ and ‘B’] in the Command Technologies HF-2500 teardown and rebuild by Steve G0UIH – Vortex Antenna Systems/Q82.uk. Here in Part 5, we remove the old receive and transmit relays. These are located on a small sub-PCB on the rear panel. We also inspect and install the new RS Components rotary switch.
The original relays are Shrack/Tyco RP710012 units. These are 16A, SPDT relays but are now obsolete [As of June 2026]. After a search online, I found a drop in replacement being the same 8 pin layout and 12v 16A handling by Omron/GE.
These new G2R-1-E-DC12 SPDT units are freely available from places like RS Components, Mouser etc for only a few ££ or $$.
See the Video Part 5a – RX/TX Relay Replacement and New Rotary Switch Intro
See the Video Part 5b – New Relays Fitted & Re-assembled – Main Band Switch Assessment
Click on any of the images below for a larger hi-res version.
See the VERY IMPORTANT note on the Violet Wire in Update 6
This is a 2 pole 2×6 position unit. We only need 1 pole and 6 positions
Brown = 10m, Violet = 15m, Orange = 20m, Yellow = 40m, Grey = 80m and Blue = 160m
These switch the small signal relays located in the rear tuning unit
