The 2003 ARRL Handbook shows a design by NC6A for sequenced switching
of a transverter. I have an HT-40 and SX-140 with manual
Standby/Transmit control by one from the other. Looks like the NC6A
circuit (Chapter 22) should work for variable hang-time pseudo-QSK
keying.

Comments?

Ted KX4OM