K2 - Bar Graph Erratic - New symptoms

[Robie Elms-2]

I posted several days ago about the bar graph (s meter & w meter) on my K2
was erratic.  I received suggestions suggesting changing the RF gain
control and re-doing the S meter calibration.  Today i did the following:

1. carefully monitored the audio from K2 as the RF gain control was rotated
and found it to be smooth and without dead spots etc.

2. checked the AGC threshold and found it to be 3.8 v.  in the CAL S LO
mode found the settings to be per the S-meter alignment procedure.

3. in the CAL S HI mode i could not get segments past the 2 left most ones
to eliminate.  Left adjustment as found

4. In the transmit mode only the 2 left most segments illuminate regardless
of the power setting.  Placing the Display in RF mode the output power
varies smoothly from 0.1 to well over 10 watts.  However, the bar graph
never illuminates more than the 2 left most segments.

5. this seems to suggest an issue with the front panel board associated
with the bar graph display.  Any suggestions on next steps, what to look
for on the board or other ideas?

Thanks in advance,

Robie - AJ4F
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[Robie Elms-2]

This problem has been resolved.   I was able to identify a poor solder
joint on the bar graph IC.  Reflowing the joint solved the problem.

73,

Robie - AJ4F

On Sat, Apr 27, 2019 at 8:57 PM Robie Elms <[hidden email]> wrote:

> I posted several days ago about the bar graph (s meter & w meter) on my K2
> was erratic.  I received suggestions suggesting changing the RF gain
> control and re-doing the S meter calibration.  Today i did the following:
>
> 1. carefully monitored the audio from K2 as the RF gain control was
> rotated and found it to be smooth and without dead spots etc.
>
> 2. checked the AGC threshold and found it to be 3.8 v.  in the CAL S LO
> mode found the settings to be per the S-meter alignment procedure.
>
> 3. in the CAL S HI mode i could not get segments past the 2 left most ones
> to eliminate.  Left adjustment as found
>
> 4. In the transmit mode only the 2 left most segments illuminate
> regardless of the power setting.  Placing the Display in RF mode the output
> power varies smoothly from 0.1 to well over 10 watts.  However, the bar
> graph never illuminates more than the 2 left most segments.
>
> 5. this seems to suggest an issue with the front panel board associated
> with the bar graph display.  Any suggestions on next steps, what to look
> for on the board or other ideas?
>
> Thanks in advance,
>
> Robie - AJ4F
>
>

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