Which cables are used to provide power to TUUAM units in 24V Lightweight FFRs?

[mikesteven]

Hi, I recently bought a wing box/arial for my 1977 FFR 24V essentially for cosmetic purposes, but it also came with a TUAAM unit which I think works. However, I'm at a loss as to which cables I should buy to power it up. I've attached a couple pictures including one of the 7 pin socket which I assume is the power socket.

 

Also, if I got it working, could I connect a CB to it?

 

thanks

mike

[g0ozs]

Mike

 

The TUUAM got power and control signals through the 7 pin cable and the radio frequency input was the BNC coaxial cable. The other end in the back of the FFR went to an ARFAT which is an adapter to use the TUUAM (a RACAL BCC product from the same family as the RT351/2 manpacks) with the much more powerful Marconi RT353. The TUUAM can also be used with a clip-in 351/2 and an Initiate box which just has a "tune" button to be pressed after changing frequency.

 

The TUUAM covers 30 to 76 MHz whereas most variations of CB are between 27 and 28MHz so it would be unwise to use them together. The CB can work with a whip cut to length because of the limited frequency range whereas the military needed the TUUAM (Tuner Unit Automatic Antenna Matching) to cover the much wider military VHF band without changing antennas.

 

I would probably bypass the TUUAM and connect the CB directly to the antenna base and make up a 1/4 wave of Clansman rods cut to length. Note also that the antenna base for the TUUAM would have contained a cylindrical section which contains a transformer that is really part of the TUUAM circuit. The cylindrical section should be removed and the inside of the antenna lead connected to the centre of the antenna base (and the screen grounded as near to the base as possible) in the same manner as for a HF radio, when bypassing the TUUAM.

 

Regards

 

Iain

[mikesteven]

thanks Iain for such a detailed and considered reply - I've learnt a lot!

 

mike