[Elecraft] Transmitting while listening in diversity mode

[Scott Ellington]

If the power coupled to the RX antenna is too high, or you just want to be safe, add a small relay in the RX antenna feedline to disconnect it and ground the RX input on transmit.  Radio Shack 275-241 works well.  I run the 12V coil on 70 V, with a series resistor, to make it switch faster, but it would probably be fast enough for QSK on 12 V.  A reed relay would probably be barely audible.

If the sound of the relay bothers you, the same can be done with PIN diodes, though it's a bit more complicated. One could probably just copy the circuit of one of the switches in the K3.


73,

Scott  K9MA




Scott Ellington
Madison, Wisconsin
USA