[Elecraft] RFI

[K5RC]

I have two identical (sequential serial number) K3's connected via a
MicroHAM MK2R for SO2R control. The left K3 has clean, clear monitor audio
on the headphones. The right K3 has an annoying level of RF garble on SSB in
the monitor audio, even with the monitor level at zero. The only difference
between the radios is the offending one has the 6M preamp, but it makes no
difference if the preamp is connected or not. The problem is not frequency
dependant. It is the same at 10 watts barefoot or full power with the amp
running. Plugging the mic and headphones directly into the K3 does not fix
the problem. I've disconnected all cables except antenna, band decoder and
CAT and the effect is the same. I've tried several different headphones as
well. The RFI is not getting on the actual transmit audio, just in the
monitor.

It really sound like the problem is internal to the radio. Any ideas?

 

Tom Taormina, K5RC

Virginia City NV

Home of W7RN and K7RC

 <http://k5rc.cc> http://k5rc.cc   FOC 1760

"Communication is the problem to the answer" - 10cc