SARBE-5 and 80cm Loop Antenna

I have now received the SARBE-5 (BE375). It is complete, with safety pin and antenna, but it has some internal damage that requires repair, this being a stuck fixing screw (however the stud had broken off so it isnt hampering anything), and a loose, and hence broken connections, antenna socket.

This is a twin UHF unit, with 243MHz primary and 282.8MHz auxiliary channels. In the case of this radio then, unlike the V/UHF SARBE-6, the two channels are entirely independent of each other - there are two Tx crystals, and two Rx sections. This gives me the option of re-tuning the receivers for two different monitoring frequencies.

My first task then, will be to repair the antenna socket. My second task is to ascertain what the battery terminal connections are! That said, I can temporarily connect the bench PSU to the internal battery connection posts. This should allow me to test the unit using the BITE functions, even without a working antenna connection.

One thing I am interested in, is how the safety pin actually works? It was my thought that withdrawing the pin, activated the beacon by 'pulling' the on/off switch around 90° so that its magnets aligned with the reed switches, but the pin is a flat bar, and slots into the control switch with it in the 'ON - MAIN' position. At this stage I can only think that the metal of the safety pin somehow modifies the magnetic fields.

Another slight issue with it is that at some point it has had a horrible sticky blue paste added to the seals. The original seal is cork gasket sheet, which I can still get from my local auto spares supplier. Since my car is due its service and MoT, I will be visiting them anyway for filters etc, so will pick up some gasket sheet at the same time.


I now have the 80cm loop antenna working, after a fashion. It is hung up on a curtain rail near the radios, and feeding my FRG-100. Im finding however a great deal of impulse noise across HF. Now, im not convinced this is an issue with the antenna itself, as im also getting this when working mobile HF, even with the engine off, but it is making testing rather trying. I can however notice the directionality of the antenna. Some investigation is needed into the source of this horrendous impulse noise.