You really don't need receiver muting for c.w. QSK,
just a receiver who's AGC can be turned off, or is very fast.

I ran QSK with a crummy Lafayette HE-80 receiver,
a B&W model 380 electronic TR switch, and a Heath Apache transmitter,
all sharing a dipole. No keying relays used at all.
If I zero-beated a station, I could just
monitor my sending with my own receiver. For split frequencies,
turn up the volume on the keying monitor.

The point of the electronic TR switch is that it acts as a preamp
for the receiver, until you transmit. Then, the tube in the TR switch
is cut off due to its high value grid leak resistor, which protects
the receiver's input stage. The signal is still loud, but if you
switch the AGC off, you can hear a breaking station between dits.

If your transmitter final is biased off during key up,
you won't hear the white noise in the receiver. If your transmitter
uses an AB1 or AB2 final for c.w., you may need
to increase the final stage bias a bit in c.w. mode,
to lower the quiescent plate current.

If white noise is still present, you can use a separate antenna
for the receiver/TR switch combination. Don't forget to use
a coax low pass filter between the electronic TR switch
and the antenna, or you will generate TV interference.

73,
Ed Knobloch

I know that I can buy a Century 21, HW-16, or Argonaut and have just
as good a CW QSK experience but I want to use a separate receiver.

Seems that at least one of the QRP CW transmitter kits would include
QSK circuitry to TR and mute a receiver.

de ah6gi/4 I have the receivers, I just need the transmitters.