[Elecraft] K3 RF feedback

[Georges Ringotte F6DFZ]

Hi to the group

Just to report a problem I had very recently.

My K3 is used with a Turner +3 microphone and had been working very fine since the beginning.

Yesterday, barefoot at 90 W or at 350 W with my PA, I had very bad modulation reports on 40 m.
I switched on the monitor, and indeed modulation was extremely bad. But it was not permanent, only from time to time.

Gary suggested RF feedback with eventually a problem from the power supply.

I checked this reflector and found Pin 1 problem syndrome.

On mine, shielded mike cable was connected to Pins 1/7, ant PTT to Pins 2/8.

I modified the Turner +3 to have the PTT ground internally connected to the mike case and mike cable shield.

Inside the K3 mike plug, I disconnected the PTT ground from Pin 8, which became free.

This seems to solve the problem.

Thank you for the Elecraft support team, and also for the fine advice on this reflector.

Best regards

Georges F6DFZ