[RFI] HI CUR warning on K3

[Pete Smith N4ZR]

I send a few characters of CW into my Carolina Windom on 40M and after a 
delay (1-5 seconds after I stop sending) the K3 flashes a HI CUR 
warning, and the audio gain is reduced significantly.  Touch the AF gain 
control and it instantly returns the gain to normal, but frequently the 
HI CURR warning returns over and over, without any additional 
transmissions.  This sequence does not happen, even with 1500 watts, 
into my dummy load, nor does it happen on the same antenna on 80M, or on 
20 meters on my tribander.

I've read the HI CUR warning discussion on page 65 of the manual, but it 
doesn't seem relevant, because I don't have external speakers.  The fact 
that it  only happens when feeding an actual antenna on one band 
suggests RFI, but the fact that the HI CUR warning and gain reduction 
recur again and again long after any RF has me puzzled.  Any suggestions 
gratefully accepted!

-- 
73, Pete N4ZR