RE: [Elecraft] Help - XFIL doesn't work -problem solved
Don, Your experience, expertise and advice does it again. Since my K2 has worked fine since I built it a year ago, I didn't think that this would be a solder problem, especially since the problem surfaced when installing the KPA100. Tom, N0SS, suggested that I re-do the BFO calibration, as you did. Re-doing the BFO range check the other day showed that the lower end of the range was above the limit by several kHz and re-setting the filters with Spectrogram didn't improve things. Then last night I resoldered all of the components used in the BFO and IF filter. Doing the BFO range check again, it was now right where it should be. Running CAL PLL and resetting the filters with Spectrogram brought my K2 back to it normal operation. So, apparently there was a marginal solder joint that was loosened by all of the moving and shaking associated with installing the KPA100. Thank you so much, and to Tom also, for your help and advise. Bob W1SRB PS - the Rework Eliminators again showed their value. I had to remove the DSP board to get to one of the test points, and I removed the SSB and noise blanker boards to re-solder the BFO and filter components. It took all of about 15 seconds to put the unheaders back in place of these boards so I could test the BFO and filters, both before and after the re-soldering effort. -Original Message- From: Don Wilhelm [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 8:32 PM To: Solosko, Robert B (Bob); elecraft@mailman.qth.net Subject: RE: [Elecraft] Help - XFIL doesn't work Robert, Did the base K2 receive OK before you added the KPA100? - note that the KPA100 has nothing to do with the base K2 receive, but I would like to know if it worked fine at one time in the past. The most likely thing that would cause the filter settings to fail is a failure of the BFO or a failure in the IF filter itself. My vote is on the BFO - go back to page 62 of your manual and re-do the BFO range test. If that is OK, then try to re-do the filter alignment using Spectrogram. Should you notice strange results with the filter alignment, then check all the components in the lower center portion of the schematic sheet 2 of 4 for proper soldering and proper component placement. The most probable cause of failure is a bad solder connection. First thing is to check the soldering, then re-check the soldering. When you have completed that, check the soldering! Often another pair of eyes will see something that you have overlooked numerous times - if you can find someone else to review your work, that may prove revealing. 73, Don W3FPR -Original Message- Then, on CW I tuned in a strong signal, and because there was lots of QRM, hit the XFIL to a narrower filter, and the signal al shifted up a lot in frequency and almost disappeared. It did completely disappear with a still narrower filter. Going to SSB, there were lots of signals, but none of them were intelligible. Checking the XFIL menu setting, they were all still as I had set them, so this isn't a menu problem. I then removed the KPA100 and the XFIL problem was still there. The next step was to see just what the filters were doing using Spectrogram. The broadest CW filter, which I had set to 1.6kHz, was more like 2.6 kHz (which explains the QRM). The other filters, which I had set to 1.0, 0.6 and 0.3 kHz were also about 30% broader and were all centered around 1.4kHz. For these filters, changing the BFO down to a setting of 0 moved them down only to about 750Hz and there was no way to get them down to 600Hz. The LSB filters were similarly messed up, with really messed up filter shapes. I adjusted them as I could. Plugging in my antenna, CW signals were a little more readable, but not much, and SSB was still unintelligible. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] Help - XFIL doesn't work
Keith, I did add the Rework Eliminators when I built the K2, and it made adding all of the internal options a breeze (KDSP2, KNB2, K160RX, KSB2 and now the KPA100) - I highly recommend them when building a K2. The problem I encountered with the KPA100 was my own inattentiveness when installing the KPA100 into the K2 and not watching where the 12V power wire from the KPA100 was (it just plugs into the K2 - nothing related to the REs). Bob -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Darwin, Keith Sent: Monday, November 13, 2006 2:33 PM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] Help - XFIL doesn't work I wonder, once this gets figured out, if we'll find that having the Rework Eliminators (so as to avoid pulling the K2 board out once it is done) would have avoided the problem ... Just thinking. Enjoy it as I'm not always known to do it :-) - Keith N1AS - -Original Message- From: Solosko, Robert B (Bob) Sent: Monday, November 13, 2006 10:43 AM ... I finished the KPA100 over the weekend ... and in the process, broke something in the K2. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: [Elecraft] Help - XFIL doesn't work
Robert, Did the base K2 receive OK before you added the KPA100? - note that the KPA100 has nothing to do with the base K2 receive, but I would like to know if it worked fine at one time in the past. The most likely thing that would cause the filter settings to fail is a failure of the BFO or a failure in the IF filter itself. My vote is on the BFO - go back to page 62 of your manual and re-do the BFO range test. If that is OK, then try to re-do the filter alignment using Spectrogram. Should you notice strange results with the filter alignment, then check all the components in the lower center portion of the schematic sheet 2 of 4 for proper soldering and proper component placement. The most probable cause of failure is a bad solder connection. First thing is to check the soldering, then re-check the soldering. When you have completed that, check the soldering! Often another pair of eyes will see something that you have overlooked numerous times - if you can find someone else to review your work, that may prove revealing. 73, Don W3FPR -Original Message- Then, on CW I tuned in a strong signal, and because there was lots of QRM, hit the XFIL to a narrower filter, and the signal al shifted up a lot in frequency and almost disappeared. It did completely disappear with a still narrower filter. Going to SSB, there were lots of signals, but none of them were intelligible. Checking the XFIL menu setting, they were all still as I had set them, so this isn't a menu problem. I then removed the KPA100 and the XFIL problem was still there. The next step was to see just what the filters were doing using Spectrogram. The broadest CW filter, which I had set to 1.6kHz, was more like 2.6 kHz (which explains the QRM). The other filters, which I had set to 1.0, 0.6 and 0.3 kHz were also about 30% broader and were all centered around 1.4kHz. For these filters, changing the BFO down to a setting of 0 moved them down only to about 750Hz and there was no way to get them down to 600Hz. The LSB filters were similarly messed up, with really messed up filter shapes. I adjusted them as I could. Plugging in my antenna, CW signals were a little more readable, but not much, and SSB was still unintelligible. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com