[Elecraft] K2 intermittent problem

[Igor Sokolov]

The problem was finally tracked down to X3,X4 crystals. Changing one of them 
(only one was found in a local shop) cured the intermittent frequency 
change. BFO frequency range is within the accepted limits (a bit more then 
3.6 kHz). VFO linearization and CAL FIL is done. Now I have  another 
problem. TX and RX frequencies do not coincide. The difference is band 
dependant. It is 30Hz on 80m and 260Hz on 28 MHz. Although the radio is 
usable with engaged RIT (OR XIT) I would like to cure the new problem.
Can somebody root me in the right direction please

73, Igor UA9CDC

----- Original Message ----- 
From: "Don Wilhelm" <w3fpr at embarqmail.com>
To: "Igor Sokolov" <ua9cdc at gmail.com>
Cc: "Elecraft Reflector" <elecraft at mailman.qth.net>
Sent: Sunday, April 08, 2012 7:26 PM
Subject: Re: [Elecraft] K2 intermittent problem


> Igor,
>
> An intermittent problem of that nature is usually associated with a bad 
> solder connection.
> Reflow the soldering (adding a little bit of flux from new solder) with a 
> hot (400 degC) iron.
>
> 73,
> Don W3FPR
>
> On 4/8/2012 4:28 AM, Igor Sokolov wrote:
>> Just discovered that knocking RF board in the region of the K14 and K15
>> relays makes the problem to appear or disappear. The offset does not 
>> depend
>> on the CW pitch  setting and is close to 1 khz.
>>
>> __________________________________________________________
>> My K2 developed a problem. In CW mode TX frequency is off the RX 
>> frequency
>> by about 1 kHz. The problem is intermittent. Sometimes it manifests 
>> itself,
>> sometimes it does not.
>> Can anybody give me a hint where to look? I was about to see if changing 
>> CW
>> pitch changes the offset but so far cannot make the problem to appear 
>> again.
>> So far there were no evidence that the problem is temperature dependant.
>>
>> 73, Igor UA9CDC
>>
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