[Elecraft] K3: KPA100 Squeal

[Guy Olinger K2AV]

Check to make sure that the cables routed in front of the fans are not
touching.  A light touch will result in a sound like that.  It will
change or go away with the fan speed.

73, Guy.

On Mon, Jun 27, 2011 at 9:10 AM, Adi Andrei <e.adi.andrei at gmail.com> wrote:
> I have the same thing happening, similar series K3 (5k something) , also assembled in March.
>
> Adi
> 2E0TTX
>
>
> On 27/06/2011 13:38, Joe Harris wrote:
>> I have very similar symptoms in my K3/100 (SN 5284) that I assembled in
>> March. It makes the sound even if I am in TX test mode. Again, no
>> performance issues, just a slightly bothersome squeal / whine.
>>
>>
>>
>> On Sun, Jun 26, 2011 at 8:23 PM, Geoffrey Wolf<liltechdude13 at gmail.com>wrote:
>>
>>> First off it was a great Field Day and my new K3 impressed me extremely not
>>> only in performance but in it's functionality.
>>>
>>> To kick off Field Day I installed a new KPA100 into the K3. I did all the
>>> necessary TX gain calibrations using a dummy load.
>>>
>>> One thing I noticed immediately was that I was hearing a very high pitched
>>> squeal coming from either the PA board or possibly the KIO3 (the board the
>>> amp plugs into). The squeal seems to vary in frequency each time the
>>> transmitter keys up (can only hear it when the radio is in TX). The squeal
>>> is not very loud but its loud enough for me to hear it if I listen closely.
>>> It doesn't seem to be power related. The squeal is there even if the radio
>>> is in TX but no power going out (RF Pwr set to 0W). The closest thing I can
>>> compare the sound to is perhaps a tiny leak in an air hose. Is this typical
>>> of a bad solder joint or something?
>>>
>>> This squeal only pertains to the new KPA100 installation. Before the amp
>>> was installed I didn't hear a thing.
>>>
>>> I should also note that nothing appears to be affecting performance. Puts
>>> out 100 watts no problem. Clean modulation, etc.
>>>
>>> --------------
>>> Geoffrey Wolf
>>> AB3LS (Amateur Radio Callsign)
>>> University of Pittsburgh '14
>>> grw20 at pitt.edu
>>> Liltechdude at me.com
>>>
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>>
>>
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