[Elecraft] K2 Faulty menu switch?

[w2bvh]

Had similar flaky symptoms on my 23 year  old K2. After careful visual 
inspection it turned out to be a broken solder connection on the tuning 
encoder. Wire barely broken off the encoder pin. Took 23 years to break!
--Lenny W2BVH

On 10/15/2022 5:36 PM, Don Wilhelm wrote:
> Jerry,
>
> That does sound like it might be a bad solder connection.
> Try resoldering Front Panel RP1 and U2.  Those components are critical 
> to decoding the switch matrix.
> You might also try reseating Control Board U6 - but do so in a static 
> controlled manner.
>
> With that 7xxx serial number, you might instead have a problem with 
> the FP Encoder board contacting the back of the Control Board which 
> causes "strange things" to happen.
> Flush cut all leads on the encoder board (right through the solder 
> fillet) and also on the Control Board where the encoder board could 
> contact.
> As an extra measure, put an insulator (fish paper is best, but a piece 
> of card stock or better yet, a piece of flat plastic (like from many 
> forms of plastic packaging) between the encoder and the control board.
>
> 73,
> Don W3FPR
>
> On 10/12/2022 5:51 PM, Gerald Wolczanski wrote:
>> from KI4io - Jerry Wolczanski
>>
>> My K2 started exhibiting this problem in June and it's gotten worse.
>> The LCD toggles rapidly between the frequency and the last menu used.
>> A tap on the menu switch restores the display to normal.  It was quite
>> infrequent to start, but now it's bothersome, happening every 10 - 15
>> minutes.
>>
>> I re-flowed the switch contacts on the front-panel board this morning,
>> but the problem persists.
>>
>> Is this a switch issue or something else?
>>
>> K2 S/N 7xxx
>>
>> KI4IO
>> Jerry Wolczanski
>> Warrenton, VA
>>
>
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