[Elecraft] K2 Faulty menu switch?

[Don Wilhelm]

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
>