[ARC5] muting

[David Stinson]

In the original design, the receiver is "muted" for full-break-in 
keying
by a relay that simply disconnects the audio output.
The receiver can take it and it works well.
All my sets are operated in original complete configuration and
I worked SKN that way without trouble.
To "net" the receiver to the transmitter, just leave the audio 
connected
and "zero-beat."
If you don't want to use a relay, one of our "smart people" can
design a simple transistor circuit that will mute the receiver 
audio
on key-down.

On your unmodified transmitter:
Please consider that any drilling or chopping will severely 
degrade its value.
The only "mods" needed are to remove one wire from the Antenna
Select relay on the front inside of the transmitter and to roll 
the antenna
spring contact around to make contact with the antenna post.

Adjust the under-chassis Selector relay to ground the 1625 
cathodes
an instant before the Osc. is turned on and use this relay for 
keying.

If you don't have an original connector for the rear, these holes 
can
be soldered because they are female and easy to clean-out later.

Assuming the bathtub cap on the back skirt is OK (do test it),
put a 50-75 pFd 1KV capacitor good for RF at the antenna post
and use it to feed your 50-ohm antenna.

That's it.  Your transmitter is preserved from destruction and
ready to get on the air.

73 DE Dave AB5S