Need help for sick K1
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Matt,
No 400 Hz tones are transmitted by WWV - you may want to check their format webpage for full information, but the tones are 500 and 600 Hz on alternate minutes with 440 Hz being transmitted the 2nd minute after the hour except that the 440 Hz tone is omitted during the first hour of each day. Minutes 0, 8 to 10, 29, 43 to 51 and minute 59 of each hour have no audio tone. The format for WWVH is slightly different - (their tones are on different minutes than WWV), check http://www.tf.nist.gov/timefreq/stations/iform.html#stdf for full details on both. The 100 Hz subcarrier carries BCD time data and is broadcast continuously. I would hate to hear that someone mistuned their K2 reference oscillator just because they did not have the current WWV tone format information available. 73, Don W3FPR > -----Original Message----- > > > There are three different signals on WWV 100, 400 & 500 Hz. I assumed > that if those signals had the proper relative frequencies that all I > had to do was check the absolute frequency. The Elecraft 2T-gen fit > that requirement with its two frequencies of 700 & 1900 Hz. > > I prefer the PSK31 waterfall display to that of Spectrogram as the > trace readily shows any drift (there is none, but it's the warm fuzzy > I'm after). > > > On Mon, 24 Apr 2006 19:44:16 -0700, Darrell Bellerive <[hidden email]> > wrote: > > >On April 24, 2006 01:56 pm, Matt Osborn wrote: > >> WWV provides a BCD subcarrier at 100Hz that is always present. Using > >> HRD's PSK31 (it's free; thanks Simon!) it is a simple matter to adjust > >> the tuning to the proper frequency. _______________________________________________ Elecraft mailing list Post to: [hidden email] 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: K2 Calibration using WWV
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In reply to this post by k6dgw
Fred, K6DGW wrote:
So ... running my K2 is like flying an F-16 or F-117A. I don't actually "control" the aircraft or radio, I "request" the computer to control it for me and hope it is listening? ------------------------------- Right, Fred, but notice that's what you did with your SX-28 too! You turned the dial to make a frequency mark line up with the indicator. That was "requesting" a frequency. The only thing you knew for certain was that it wasn't exact! The same is true of the K2. The difference is that the K2 is a lot closer than almost any analog system at any price. When you calibrated your SX-28, you were setting it so the requested frequency equaled the actual frequency as close as possible. But you knew that even at the reference frequencies you use to calibrate the receiver it wasn't exact. That's similar to the problem with the K2's inability to be absolutely exact to the Hz in establishing the exact tuning when you run CAL PLL even if the 4 MHz clock is exactly on so the frequency counter function (FCTR) in the K2 is "dead on", there's still the problem of deciding exactly what is "on frequency". In the K2 it's not a matter of reading a line on a frequency scale but instead is a matter of how accurately the DACs can read the tuning voltages being applied and record their value in memory. Then when you tuned in WWV later on your SX-28, there was the issue of deciding exactly when the frequency mark was aligned with the index. You can get very close, there's a limit to how "exact" you can be. That's like tuning in 10000.00 on your K2. The DACs then have to create the tuning voltage by the data in memory for that frequency, but there's a limit to how close they can replicate it, just as there's a limit to how close you can reposition the dial at 10000.000 MHz. The lines on the SX-28 dial have to have width so you can see them. There's a limit to how exactly you can position the pointer once the receiver is exactly tuned to the reference source, like WWV. The K2 has a tuning resolution of 10 Hz. That's like saying the K2's 'dial markers' are 10 Hz wide! And, finally, even if you did get the dial set exactly on 10000.000 Hz on your SX-28 and you had calibrated it with the same accuracy, you are still at the mercy of any drift in the oscillator frequency since you calibrated it! The same is true of the K2. It will change a little with temperature and time, although those oscillators are very stable! One thing the K2 can't match on your SX-28. Those human-friendly knobs, especially those honkin' big hand-wheels used for the main and bandspread tuning!! Sigh!! But then I don't need a fork lift to pick up my K2. People who groan when they hoist an Astron 35 amp power supply never carried an SX-28 around. Still, if I ever come across one that I can afford... Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Douglas Todd
In a message dated 4/25/06 7:12:19 PM Eastern Daylight Time,
[hidden email] writes: > Fred, K6DGW wrote: > So ... running my K2 is like flying an F-16 or F-117A. I don't actually > "control" the aircraft or radio, I "request" the computer to control it > for me and hope it is listening? > > ------------------------------- > > Right, Fred, but notice that's what you did with your SX-28 too! You turned > the dial to make a frequency mark line up with the indicator. That was > "requesting" a frequency. I disagree! With the SX-28 or similar receiver, you actually adjusted the LC tuned circuits and other parameters yourself. You didn't "request" anything - you changed the parameters directly. With the K2 or other processor-controlled rig, you send a request to the processor, and *it* figures out how to change the LC tuned circuits and other parameters. Both systems have advantages and disadvantages. All depends what tradeoffs you choose. btw, although the K1 has a processor, it's closer to the SX-28 in basic design (!). -- One thing that I find somewhat amusing is the enoromous attention given to getting exact QRG down to a few Hz. For specialized uses, that sort of accuracy might be needed, but I'm much more interested in things like dynamic range, selectivity quality, etc. - differences you can hear! 73 de Jim, N2EY _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Ron D'Eau Claire-2
Ron D'Eau Claire wrote:
> Right, Fred, but notice that's what you did with your SX-28 > too! You turned the dial to make a frequency mark line up > with the indicator. That was "requesting" a frequency. Well, I was just sort of reflecting on our world. Wilbur and Orville would be astounded. Marconi would be too, as would Watson and Alexander if they met my grandsons and watched them pull their "telephone" out of the pocket in their oversize cargo shorts. I just counted, and I don't have a working radio in my shack ... OK any radio ... that doesn't have a computer in it. > The only thing you knew for certain was that it > wasn't exact! Truth be told, "exact" didn't matter then. I tuned to what I wanted to hear, not always inside the ham bands. But your observation is correct. Nor did doing a CAL PLL on my SX-28 on WWV at 10 MHz assure that 15 MHz would be even close to right. > And, finally, even if you did get the dial set exactly on > 10000.000 Hz on your SX-28 and you had calibrated it with > the same accuracy, you are still at the mercy of any drift > in the oscillator frequency since you calibrated it! I never turned my radios off. I told my Mom they were in "standby mode" and consuming 0.1 kilowatt-hours per day, less than her kitchen clock. She didn't know what a kilowatt-hour was, she knew I did, and she liked her clock so she believed me. Left on all the time, Bill Halligan did a pretty good job with the SX-28 in the drift arena. > The same is true of the K2. It will change a little with temperature Mine seems to drift about 450 Hz from cold-start to scheduled QSO time, over maybe 30 mins which is great as far as I'm concerned. At least, that's what my service monitor tells me, which I leave on all the time too and tell my wife (the family comptroller) that it is in "standby mode" who is less accepting of my stories than my Mom was. > But then I don't need a fork lift to pick up my K2 No kidding! I had forgotten how heavy that puppy was! Took a large handtruck to get it out of Woody's family's house, and two of us to get it into and out of my shack. 73, Fred K6DGW Auburn CA CM98lw _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by N2EY
And the K1 is all the better for it too with the silkiest tuning of the
bunch. I'm also mystified by the compulsion to measure operating frequency on a ham BAND to a few Hz. Assuming I'm inside the band, the only frequency of interest to me is the person I'm in QSO with. I want to be close to that frequency, but I really don't care what that frequency actually is. A super accurate display doesn't tell me if I am on the other guys frequency...there easier ways to determine that. Maybe operating for a day with something like my Drake 2-B/2-NT would be a good replacement for the code requirement. Eric KE6US www.ke6us.com -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of [hidden email] Sent: Tuesday, April 25, 2006 5:30 PM To: [hidden email] Subject: Re: [Elecraft] K2 Calibration using WWV btw, although the K1 has a processor, it's closer to the SX-28 in basic design (!). -- One thing that I find somewhat amusing is the enoromous attention given to getting exact QRG down to a few Hz. For specialized uses, that sort of accuracy might be needed, but I'm much more interested in things like dynamic range, selectivity quality, etc. - differences you can hear! 73 de Jim, N2EY _______________________________________________ Elecraft mailing list Post to: [hidden email] 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: [hidden email] 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 |
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In reply to this post by Douglas Todd
With all this talk about calibration, I thought I'd go through the procedure
again just to check and see how ole #337 was doing. I don't remember exactly when I last calibrated it, but it has to be over a year, perhaps over two. She was 10 hz low at 10.0 Mhz checked against WWV. Didn't have to adjust a thing! 73, Randy, KS4L _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by EricJ-2
On Tue, 25 Apr 2006, EricJ wrote:
> And the K1 is all the better for it too with the silkiest tuning of the > bunch. > > I'm also mystified by the compulsion to measure operating frequency on a ham > BAND to a few Hz. It would be useful for another thing I've never understood....the exact resonant frequency of the antenna. > Maybe operating for a day with something like my Drake 2-B/2-NT would be a > good replacement for the code requirement. You could also simply be able to pass the seamanship merit badge and run Pactor and not have to worry about anything ham radio related. 73,Thom-k3hrn www.zerobeat.net Home of QRP Web Ring, Drakelist home page,Drake Web Ring, QRP IRC channel, Drake IRC Channel, Elecraft Owners Database www.tlchost.net/hosting/ *** Web Hosting as low as 3.49/month _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Darrell Bellerive
On Tue, 25 Apr 2006 09:50:55 -0700, Darrell Bellerive wrote:
> Then again, WWV >is only accurate as received to +/- 1Hz (1 part in 10 million). _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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In reply to this post by Darrell Bellerive
On Tue, 25 Apr 2006 09:50:55 -0700, Darrell Bellerive wrote:
> Then again, WWV >is only accurate as received to +/- 1Hz (1 part in 10 million). After using systems having timebases slaved to rubidium and cesium standards ("atomic clocks") where expected stability and accuracy is 1 part in 10^13, HF-WWV which is usable only to 1 part in 10^7 is downright sloppy!!! Those of us who appreciate precision readouts are no different from those of us who appreciate knowing time of day down to the second (which for some purposes is downright sloppy as well). -- 73 de K2ASP - Phil Kane _______________________________________________ Elecraft mailing list Post to: [hidden email] 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: K2 Calibration using WWV
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In reply to this post by k6dgw
Fred, K6DGW, wrote:
Mine seems to drift about 450 Hz from cold-start to scheduled QSO time, over maybe 30 mins which is great as far as I'm concerned. ------------------- Is that your K2 that drifts that much or the SX-28? I can imagine the SX-28, but the K2 should not drift more than perhaps 50 to 100 Hz from a cold start at the worst. My K2 starts out about 60 Hz off and is on frequency and stable about 30 minutes later. My HRO-5 receiver stayed on 24/7 too, at least the filament power. Not only did it keep stable that way but it was easier on the tubes and many other parts too, as you know. Of course the HRO-5 had a dial calibrated arbitrarily from 0 to 500. The operator was left to consult a graph of frequency vs. dial reading to determine where to set it for a given frequency. The graph allowed an accuracy of perhaps 25 or 50 KHz! Other means were needed to arrive at the dial setting needed for any higher accuracy. The bottom line, as you know, was that the exact frequency wasn't needed then just as it isn't needed that often for Ham activity today, except to tell where the band or sub-band edges are. Within the bands we looked for clear frequencies, not specific frequencies. If we were listening for someone to call on sked or a net, we knew enough to tune around the approximate frequency where we had expected them, not to look at an exact value. So I don't know that the extra accuracy we have in modern rigs is needed as much as it's simply a by-product of a more stable design. It still doesn't mean much in daily use within the Ham bands. Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [hidden email] 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: K2 Calibration using WWV
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In reply to this post by N2EY
Jim N2EY wrote:
With the SX-28 or similar receiver, you actually adjusted the LC tuned circuits and other parameters yourself. You didn't "request" anything - you changed the parameters directly. ----------------------------- My point is that the dial mechanism is a simple form of mechanical logic. When the operator tunes a an SX-28 so the index points to 10.000 MHz, the operator is "requesting" that frequency. The operator isn't setting the L/C network to anything he/she can see or identify at that point other than to make the index point to 10.000 on the dial. The dial mechanism moves the tuning circuit components in a way that, if the system is calibrated, will result in the receiver being tuned to 10.000 MHz, plus or minus whatever errors are inherent in the calibration or pointing accuracy of the mechanical computer (dial mechanism). Ron AC7AC _______________________________________________ Elecraft mailing list Post to: [hidden email] 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 |
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