[Elecraft] K2 KPA100 overheating/erratic fan problem

[nu6n at yahoo.com]

Hi Don,

Yes, it does have a good pad and is properly attached to the heatsink. I was upgrading the KPA and re-soldered both Q3 and U1 temperature sensing contacts as well as verified that Q3 installed properly. But that did not change anything.

73, Arkady
On Dec 1, 2020, 11:18 AM -0800, Don Wilhelm <donwilh at embarqmail.com>, wrote:
> Arkady,
>
> Is Q3 properly seated on the heatsink with its thermal pad and mounting
> screw? That is the device which senses the temperature.
>
> 73,
> Don W3FPR
>
> On 11/30/2020 5:00 PM, Arkady via Elecraft wrote:
> > Hello,
> >
> > I wonder if anybody had similar problem.
> > When I “run” I get fan starting running after 10-15 minutes. However after another few minutes of running the fan will shuts down every time I press a key ( I am CW op). As a result the temperature of the PA goes higher and higher and at certain point the PA shuts down. If I check the temperature reading through temperature calibration in the menu I see that temperature reading jumping force and back with range of readings 10 - 20C. That kind of erratic temp reading continues even when temperature of the heatsink goes down. If let the trcv to cool (overnight) the temperature readings are stable with range of reading +- 1C.
> >