[Elecraft] Intermittent loss of power output K3 - update

[Peter Lock]

Subject: [Elecraft] Intermittent loss of power output K3

Good day

Late last year, my K3 (no 6957) developed a fault.  The symptoms were:
1. No power output when keying the rig
2. TX LED on when keyed, (sidetone generated in CW mode)
3. Single bar showing on the RF power meter, whatever scale, ie 0 - 10 or 0
- 100
4. ATU tune command: relays clicking, TX LED on, no power output, no
indication on SWR meter; two horizontal dashes in the VFO A display area
where normally one would see the resolving SWR; in VFO B area 5.0W is
indicated
5. TX gain calibration failed on 5W and 50W;  mW TX calibration gain OK

Peter
M0RYB

Thank you to all who have responded to my post.  The board connection pins
are gold plated, and all look bright and shiny like new.  The TMP
connectors, however, all are tarnished on the outside, although the mating
surfaces look clean; I will get some Deoxit and give them a going-over.

The diodes D36 and D37 in the SWR bridge tested in situ showed a forward
voltage of 0.362V and a reverse open circuit, so they seem to be fine.

Peter
M0RYB