Monday, August 25, 2014

R109 Receiver

The other night I watched a programme on TV about the taking of the Arnhem Bridge during the war. It was interesting to watch and also why the mission became a bridge too far. It seems that one of the problems was the radio equipment which failed to function correctly. That meant that there was a breakdown in communication between the different troops. In the film showed one of the radio operators at Arnhem using an R109 receiver. I took some photos from my screen.

I was amazed to see this because I had one for years when I first got my Radio Amateur licence. It cost me £1.50p from a surplus shop on Folds Road in Bolton. It worked perfectly and ran from two 6 volt motorcycle batteries that I had permanently charging. The R109 had a vibrator pack to increase the voltage and also had a spare set of valves held inside the case of the receiver. The first thing that I did was to the metal guard on the front, it must have been hard for the radio operator to use this receiver with the guard fitted. I also removed some of the other things like the antenna terminals and big knob on the left that didn't seem to do anything. I fitted a coax socket for the antenna. 

Here I am operating the receiver when I was 17 years old, note the two 6v batteries under the bench and old WWII headphones.

As I watched the programme I could remember what all the switches and knobs did on the R109, it was a fine receiver and I modified it inside to make it better. I added a BFO so that I could listen to SSB signals and also an S-Meter connected to the AGC line, it worked well! You can see the BFO adjustment knob just above the microphone.
I would love to play around with some of these old receivers again!

I'm not sure what the transmitter is on the right of the R109, I don't recognise it at all.


Anonymous said...

The transmitter is a Wireless Sender 76.
I am currently restoring one

Rob said...

You speak of removing the "big knob on the left that didn't seem to do anything" - could this have actually been the bakelite watch holder, used for holding a calibrated 'Army Time Piece'rather than a knob?
Also, excuse my confusion/ignorance, but why did you add a BFO to receive SSB, when the R109 has a BFO for this purpose as part of its functional design originally?