[ARC5] Running the receiver rack with the sidetone/voice function

[J Mcvey]

Took the plunge and wired up the 6 pin plug cable that goes from the BC-456 to the receiver rack.It actaully functions pretty well , not objectionably loud on sidetone or voice. However I'm using a speaker , not headphones and I'm going to re-visit the impedance of same because I think the whole thing could be louder than it is. Right now it's set for about 600 ohms for the ARC-5 receivers.
Like all of the WWII military radio sets, this has "voice monitor on Tx. This one  runs directly off of a winding on the modulation transformer- not through the rx like the FM sets. No feedback issues. The sidetone was nice clean sounding pitch  maybe 800 hz????
The only problem with this is now I can't 'spot the tx( sync the tx /rx frequencies) ...but I have a plan....All that need to be done is to insert a switch in the "key" line that operates the rack relays so that it won't switch the audio on Tx and leaves the rx audio connected. I was also considering to have that same switch also kick in some serious antenna attenuation so the rx is not overloaded and the spot function will be more accurate.
I'm surprised that the front ends don't get destroyed with this setup! Even with the relay grounding the receive antenna , it's not enough!\It didn't seem that bad in CW, but the voice is LOUD.

I guess they never had to deal with this on the planes because the transmitters were "set and forget", not able to be tuned during flight?


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