[Elecraft] KPA100 Problem

[Mark Flavin]

Ok. I will do that.  Anything is worth a try

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-----Original message-----
From: Don Wilhelm <w3fpr at embarqmail.com>
To: Mark Flavin <markf1952 at hotmail.com>
Cc: elecraft at mailman.qth.net
Sent: Sat, Nov 26, 2011 20:05:50 GMT+00:00
Subject: Re: [Elecraft] KPA100 Problem

Mark,

If there was a marginal solder connection, it may have worked but with the  
movement involved with the upgrade, it may have finally failed.

Yes, investigate those components that I mentioned.  If the temperature is  
not being sensed, the fan will be turned on and off by the firmware because  
the firmware is not getting correct information about the actual  
temperature.

Are the thermal pads under Q3 and Q4 in good shape?  It may be worth  
replacing them if there is any question.

73,
Don W3FPR

On 11/26/2011 2:24 PM, Mark Flavin wrote:
> Thanks Don.  This thing worked before I did the upg kit.  I will check  
that
> again but I didn't really touch those.  Perhaps I will remove the   Q3 and
> check that area.  Best I can tell the upgrade didn't really address any of
> that but I don't know.  The finals don't get hot at all.  I even took the
> heatsink off to make sure there were no shorts or anything and its the  
same.
>    The weird thing is how the fan starts and stops as I key even at low  
(11
> to 15 watts) power.  I just hope its not the finals.  I don't think so
> either but I want to try everything else first.  Could Q3 just be too
> sensitive due to something.  I could try changing it I suppose.
>