Don, This is my problem. I have 120Hz drift. I have been unable to correct it and I sent my K2 to you and others without results. Let me give you an example.
I come into the shack in the morning, it is about 65 degrees. I turn on the rig. The display says 7000.004 Khz. I hit the band button and shift to 10Mhz WWV. I hit the "zero beat" button and it gives me a matching tone. I zero the main tuning knob, and it verifies that WWV reads out at 10000.004 Khz Now, I do nothing. I go back to 7000.004 Khz and I tune around the band looking for a CQ. If I don't find one in about 1/2 hour I go back to 10Mhz WWV. It now zeros at -3Hz ie. 9999.997 Khz. I adjust the zero on 40 meters to read 6999.997 KHz. Now I get lucky. I find a CQ, I crank up the power to 100 Watts and I call him. I'm not fooling around, we do a real rag chew and we talk for perhaps 30 minutes. As I notice him drifting, and my experience tells me that it isn't him drifting, it's me, I use the tone zero beat and I adjust the main tuning knob to maintain zero beat with my QSO. He stops drifting when my dial reads 7043.993 KHz. Now the QSO ends and my K2 has stabilized. I return to 10MHz WWV and my dial reads 9999.993 KHz. Thanks, K6GC, TR K2/100 S/N 838 ________________ At 05:07 PM 9/4/2011 -0400, Don Wilhelm wrote: >John, > >You are reporting a shift of 128 Hz in one case, and 117 Hz in another >case. The difference between the two is close to 20 Hz which is the K2 >BFO DAC limit, so that is not surprising, particularly if the BFO >voltage to the DAC is right on the "edge". > >Yet, I do not understand what approximately 120 Hz has to do with CW or >CWr - unless you have the K2 sitting close to an AC transformer, sine >120 Hz is twice the 60 Hz line frequency and the shift is coming from >the VFO. > >You may have some inconsistency in addressing the EEPROM. If that is >the case, it will be cured by a Master Reset - BUT record all your menu >settings before doing the reset and restore them afterwards. The K2 A >to B Instructions contain nice tables for recording the menu values, and >I encourage you to download those instructions to record the menu >parameters. > >I would suggest you use the N6KR method to set the 4 MHz reference - the >precise setting may be slightly different than exactly 4 MHz, and the >N6KR method erases any variables other than your ability to tune WWV (or >any other "standard" station) with precision in SSB mode. >For the full K2 Dial Calibration procedure, see the article dealing with >that subject on my website www.w3fpr.com. If you only want to set the 4 >MHz reference using the N6KR method and then run CAL PLL and CAL FIL, >you can refer to Wayne's document from the Elecraft reflector archives >of 8/20/03. > >Remember, setting the 4 MHz Reference Oscillator by itself does nothing >to the dial calibration, one must run CAL PLL and CAL FIL to set the new >values (based on the new setting of the Reference) into EEPROM before >any chance in tuning is made. > >73, >Don W3FPR > >On 9/3/2011 9:24 AM, John Oppenheimer wrote: > > I am a new K2 (#7212) user. I have been baffled by what I thought was my > > inability to properly perform the frequency alignments. My last attempt > > was to perform a factory reset and re-do PLL and BFO (Table 8-1 values) > > calibrations. > > > > I believe that I have found the issue, sometimes it appears that the VFO > > frequency offset look-up tables are not used and a toggle through two > > "CW REV" changes are needed. > > > > Used a K3 CWT SPOT as a 4MHz monitor to adjust C22. > > > > Using a K3, CWT, SPOT and K2 in in TUNE (with dummy load) to measure the > > K2's frequency. Test process is: > > > > Note: only the events in the below text were performed. > > > > Power off K2 with F set to 7026.00 > > Power on: K2 F=7026.00 K3 F = 7026.146 > > "CW REV" "CW REV", K3 F = 7026.018 > > Power off K2 > > Power on K2 F=7026.00, K3 F = 7026.025 > > Power off K2 > > Power on K2, Move K2 F to 7027.00, K3 F = 2027.028 > > Power off K2 > > Power on K2 F = 7027.00, K3 F = 2027.145 > > "CW REV" "CW REV", K3 F = 7027.000 > > > > I was listening to the audio during the above process. There was a > > notable change in the resulting pass-band audio when the "CW REV" "CW > > REV" toggle was performed and the K2 frequency changed. Leading me to > > believe that the VFO offset frequency was changed. > > > > Though I can't find a reproducible process, I have found events where > > during a K2 power on session, sometimes a "CW REV" "CW REV" is needed to > > acquire correct K2 frequency. > > > > Is this normal K2 operation, or do I have an issue with this K2? > > > > John, KN5L > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:[email protected] > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > >______________________________________________________________ >Elecraft mailing list >Home: http://mailman.qth.net/mailman/listinfo/elecraft >Help: http://mailman.qth.net/mmfaq.htm >Post: mailto:[email protected] > >This list hosted by: http://www.qsl.net >Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
