[Elecraft] KX3 Receive Audio & Control Knob Problems

[Robie Elms]

All,

I have acquired a used KX3 (serial number between 4000 and 5000, uC
firmware 0.150, dsp firmware 01.21) and I am checking it out.  The problem
I have encountered is no RX audio:

1. The AF/RF-SQL knob does not change either RF or AF gain.  When I TAP the
knob I momentarily see 1 in the OFS/B window then returns to VFO B.
Rotating the knob does nothing.  A second tap shows RF --58 momentarily and
then returns to VFO B,

2. WIth the MODE set to USB and tuning to 14074 (lots of loud FT8 stations
on this freq) I see S meter action.

3. When I send CW I hear a side tone from the headphone and the speaker
when the headphone is unplugged.

4. When I HOLD the AF/RF-SQL knob and go to MON the OFS/B window show 5 and
rotating the AF/RF-SQL knob does not change the number.

5. The PBT I/II knob appears to function properly.

6. With MODE set to USB rotating the Keyer/Mic knob does not produce any
indication of a change in MIC gain in the OFS/B window.  When in the CW
mode rotating the know does not change keyer speed (remains at 18 WPM),

7. When I HOLD the KEYER/MIC knob to adjust power 5.0W is displayed in the
OFS/B window.  However rotating the knob does not change the power level.

8. The KX3 transmits CW properly at 5 W output.

9. I do not yet have a USB/Serial interface to possibly reload firmware.

I'm looking for suggestions for next troubleshooting steps.


Robie - AJ4F