Re: [Elecraft] K2 Faulty menu switch?
I seem to have fixed the problem - the K2 ran for 11 hours yesterday
without a hiccup. I've got it running on the downstairs workbench this
morning and, if nothing is amiss, I'll button it up tomorrow morning.
Here's what I did, sorta in the right order:
1) Snipped the protruding wires on the rear of the encoder board.
2) Re-soldered U2.
3) Put plastic between the control board and the encoder board.
4) Re-soldered RP1 pins.
problems persisted.
5) touched up (re-soldered pads) around the damaged area.
6) Did resistance checks on all the damaged traces. While they
looked a little scruffy, all was well.
7) Re-soldered all the pads on the multi-pin (18?) connector. Note
that the U2 pull-up resistors are not on the same board as U2.
8) Gave both the control board and the front panel board a thorough
inspection. I did touch up a few solder joints here and there -
probably not necessary.
9) So it's back together at the moment, minus the front panel
which I'll install tomorrow.
Built this radio in early 2015 and aside from blowing a pair of finals
(testing antenna couplers) it has performed flawlessly. Oh yeah, I
now use a resistive bridge when tuning the open-wire feed!
Huge thanks to Don Wilhem for setting me on the right trouble-
shooting path. And big time kudos to Eric and Wayne for such an
amazing design ("look ma, no cables!").
Thanks
Jerry W
KI4IO
Warrenton VA
On Sun, 2022-10-23 at 11:35 -0400, Don Wilhelm wrote:
> Jerry,
>
> Yes I see the photo.
>
> Although it looks like the copper is intact, I would scrape away a
> bit
> of the silkscreen on each end of the damaged area and then solder a
> small gauge wire across the damage. If you have some #24 wire (from
> ethernet cable for instance) use that rather then the #22 wire
> supplied
> with the K2 kit.
> It is usually best to route the wire along the original PC board
> trace
> so you can tack it in place at several places along the way from end
> to end.
>
> Reflow the solder on the encoder board just in case that is the
> problem.
>
> 73,
> Don W3FPR
>
> On 10/22/2022 9:33 PM, Gerald Wolczanski wrote:
> > Don, indeed it was the FP encoder board touching the back of the
> > control board. I'm attaching a photo, which I guess only Don can
> > see.
> > The PCB traces are dinged up, exactly .3" apart. Two things:
> >
> > 1) Wonder if the control board or the encoder board may have been
> > been
> > damaged by these boards touching? Occasionally, in these last few
> > days, the encoder freezes up and a tap on the menu switch gets it
> > back
> > to normal. Even after I trimmed the encoder board leads and put a
> > piece of think plastic material between the control board and the
> > encoder board, I still get the occasional encoder freeze-up.
> > 2) Can I try and flow some solder on those damaged traces?
> >
> > Thanks so much for your help!
> >
> > Jerry
> > KI4IO
> > Warrenton, VA
> >
> >
> >
> >
> >
> >
> >
> > On Sat, 2022-10-15 at 17:36 -0400, 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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Post:
Re: [Elecraft] K2 Faulty menu switch?
Jerry, Yes I see the photo. Although it looks like the copper is intact, I would scrape away a bit of the silkscreen on each end of the damaged area and then solder a small gauge wire across the damage. If you have some #24 wire (from ethernet cable for instance) use that rather then the #22 wire supplied with the K2 kit. It is usually best to route the wire along the original PC board trace so you can tack it in place at several places along the way from end to end. Reflow the solder on the encoder board just in case that is the problem. 73, Don W3FPR On 10/22/2022 9:33 PM, Gerald Wolczanski wrote: Don, indeed it was the FP encoder board touching the back of the control board. I'm attaching a photo, which I guess only Don can see. The PCB traces are dinged up, exactly .3" apart. Two things: 1) Wonder if the control board or the encoder board may have been been damaged by these boards touching? Occasionally, in these last few days, the encoder freezes up and a tap on the menu switch gets it back to normal. Even after I trimmed the encoder board leads and put a piece of think plastic material between the control board and the encoder board, I still get the occasional encoder freeze-up. 2) Can I try and flow some solder on those damaged traces? Thanks so much for your help! Jerry KI4IO Warrenton, VA On Sat, 2022-10-15 at 17:36 -0400, 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 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2 Faulty menu switch?
Geeze, spent yesterday looking things over. Put a piece of paper between the encoder and the control board. Thought I'd just put the rig through its paces this morning and observe 1) Well to start, the display flipped to the "side-tone level" after a short time and a little later the encoder locked up and I was unable to transmit. In both cases, depressing the memory switch put the K2 back in operation. 2) Wondering if there was a time element involved, this morning, after the anomaly cleared, I simulated operating by tapping the key every few minutes. The rig performed flawlessly for an hour. The WSPR frequency is the perfect place to test a rig - those guys don't even know I'm there. 3) Then I just left it on, listening to the band and checking every 20 or 30 minutes, and it's performed flawlessly for 4 hours so far. 4) I don't believe in miracles - I'm mindful of Lenny's experience and Don's advice. Gonna leave the rig on and see if it acts up again. Jerry KI4IO Warrenton, VA On Wed, 2022-10-19 at 12:46 -0400, w2bvh wrote: > 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 > > > > > > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > Message delivered to w2...@comcast.net > > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2 Faulty menu switch?
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 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to w2...@comcast.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] K2 Faulty menu switch?
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 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
