[Johnson] Johnson T-R Switch Receiver muting

[WQ9E at btsnetworks.net]

Harry,

I will have to go back and look at the ER article but what is the reed relay configured to do?  If the relay shorts the SX-100 antenna to ground the receiver shouldn't be overloading. If all the relay does is ground the audio then try using the relay to bias the SX-100 into standby using the muting terminals on the receiver accessory plug.  

If all else fails, put a second reed relay coil in parallel with the first so that you can both ground the receiver antenna input and use the receiver muting circuitry.  If you are trying to operate full break in and monitor with the receiver while using the Johnson switch then add an auxiliary gain pot as used in the SX-88 receiver.  You can see this from the SX-88 schematic on Bama.  The way it works is the main RF gain control works when the receiver is not in standby and a second pot is used to set sensitivity when in standby mode so that monitoring can be accomplished.  It may be necessary to use a little series resistance with a reed relay grounding the receiver input to provide sufficient signal.

Rodger WQ9E 

-------- Original Message --------
> From: "Harry Vaught, KT4AE" <kt4ae at bellsouth.net>
> Sent: Thursday, May 10, 2012 8:24 AM
> To: johnson at mailman.qth.net
> Subject: [Johnson] Johnson T-R Switch Receiver muting
> 
> Has anyone conquered the receiver muting problem with the Johnson T-R 
> switch?  It was to be used in my Ranger/SX-100 station.
>