[Elecraft] Further heil proset question

[Ross]

Thanks for the comments, regarding my problem with the Heil proset.

I have tried running the K3 into a dummy load (plugged directly into Ant 1) with only 1 watt output,
 bias on, front panel high. At least I can hear my speech, BUT the audio moise is very loud.
Bias off, no speech, so it needs the bias.

So surely at that low power level, rf feed back should not occur, could it be a faulty headset?
Any other ideas please..

Regards
Ross
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