[Elecraft] K3 - PA Temp Unstable

[Mike Cox]

Thanks Wayne. I suspect that you are right. I'll collect the parts and 
have them ready to go if the problem starts up again. Replacing header 
pins like these is something I've done many times before so I anticipate 
no problems with the repair. This radio has performed extremely well in 
almost daily use for many years now. The fan speed/temperature 
indication issue has been only a minor annoyance that I would have fixed 
already if it weren't so intermittent.

73,
Mike

On 1/20/2014 19:06 PM, Wayne Burdick wrote:
> If you put a DMM (voltmeter) on the associated pin, you should see the voltage changing (a few mV, probably). You can easily get at these pins by taking the bottom covers (A and B) off the radio. Chances are that the old, non-gold pins on the front panel module are the cause.
>
> 73,
> Wayne
> N6KR
>
> On Jan 20, 2014, at 7:16 AM, Mike Cox <mike at ab9v.us> wrote:
>
>> I'd like to see how this is resolved. I note the silence about it after your post.
>>
>> My early K3 (sub s/n 500) started doing this same thing intermittently several months ago. The problem occasionally got bad enough that the rig would cut back to low power mode and report the PA over temperature.  The problem would manifest itself upon power up after the radio had been off overnight. Usually within and hour after power-up the PA temperature report would stabilize and all was well. I pulled the PA board off and did the gold pin replacement but this did not resolve the issue. A month or so later, the temperature report stabilized. I have not yet pulled the front panel to change out to gold pins in that area. As the radio has not exhibited this behavior for the past month, I'm holding off until I can tell that I've fixed it (or not) when I work on it. I love repairing intermittant issues (not!). Anyway Paul, your problem is not unique.
>>
>> 73,
>> Mike, AB9V
>>
>> On 1/18/2014 3:41 PM, paulb wrote:
>>> Hi  folks
>>>
>>> K3 here owned for about 4 years.
>>> Latest firmware.
>>> Last couple of days at power up the PA Temp is unstable.
>>> LCD flicks between 27 and 40 degs C.
>>> TX and RX same reading.
>>> Noticed the rear fans starting and stopping
>>> Reloaded firmware no change.
>>> Before lifting the hood anyone got a pointer what to
>>> check ?
>>>
>>>
>>> thanks
>>>
>>> cheers
>>>
>>> Paul b
>>> zl1ajy
>>>
>>>
>>>
>>>
>>>
>>> --
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