[Hallicrafters] B&W TR Switch....Maybe I got it wrong!

[Dave Moorman]

on 6/8/02 5:24 PM, Parker Buckley at buckley at iapdatacom.net wrote:

> Following my original posting, I've received a couple of messages
> telling me to hook up the mute line from the transmitter to the
> receiver.  I thought the B&W unit would effectively block the signal to
> the receiver so I didn't need the mute line, thus allowing full break-in
> keying (internal transmitter relay stays closed the whole time and
> un-muted receiver stays active between cw characters).  I'm using the
> mute line at present with a conventional Dow Key relay, so it's no
> problem using it with the B&W unit.....I guess I misunderstood
> (overestimated?) the function of the B&W unit!
> 
> Thanks for the replies.  I'll try it that way and perhaps dust off the
> QST plans for the Bug Box QSK project, which uses a vacuum relay.
> 
> 73,
> Parker WD8JOL

I used the Johnson TR switch for many years, and, if memory serves, muted
the receiver by switching some more resistance into either or both an RF amp
and the audio amp cathodes.  That muted the receiver and the output was at a
comfortable level for monitoring.  When the key was up full sensitivity
restored very quickly.  It was all done electronically - solid state,
though.  

Dave