[Elecraft] K3 Receive De-sense Problem

[Vic Rosenthal 4X6GP/K2VCO]

Hank, check the grounding of the SO239's. I believe the path is through 
some hardware. Also don't absolve the patch cables too quickly.

On 13 Mar 2015 06:30, Hank Garretson wrote:
> For the past few months, I have had intermittent receive de-sense with my
> K3/100-F, Serial 1523. Firmware 5.14, 2.13, 1.19 installed this week, but
> de-sense was there with previous firmware.
>
> Intermittently receive sensitivity will drop about ten dB. Usually happens
> after transmitting, but sometimes happens spontaneously with no
> transmitting. A dit usually restores sensitivity. If I don't dit,
> sensitivity randomly restores itself.
>
> CW, SSB, RTTY. All contest bands. (Don't do WARC.)
>
> I have one-by-one eliminated my BCD antenna-switches, my ACOM amplifier,
> and my antenna/dummy load switch. With these items in or out of line, I
> still get intermittent de-sense.
>
> Which leads me to believe the problem is with the K3 itself. (It could be
> one of my coax patch cables, but I suspect not.)
>
> KXV3 installed, but use ANT1.
>
> SUB installed. Intermittent de-sense with and without SUB engaged.
>
> Suggestions?
>
> 73,
>
> Hank, W6SX


-- 
73,
Vic, 4X6GP/K2VCO
Rehovot, Israel
http://www.qsl.net/k2vco/