Hi Don, I think the Heathkit clock was more sophisticated. It read the 100hz data code and automatically set the hour, minute, seconds, and date. It did all of this using an on-board microprocessor. I've never owned one, so I'm basing my information on the blurb here: http://wd6cmu.antennalaunchers.com/gpsclock.htm
The NBS 668 method is a more manual process. First, you set your clock to within a second by listening to the "at the tone" message and pushing the button when you hear the beep. Then, you make small +/- phase adjustments it until the 1Khz "tick" pulse appears where you expect it to be on the scope. Thanks, -JP On Sat, Dec 19, 2009 at 2:01 AM, Don Latham <[email protected]> wrote: > Is this the basis document for the Heathkit Most Accurate Clock??? > Don > > ----- Original Message ----- From: "Justin Pinnix" < > [email protected]> > To: "Discussion of precise time and frequency measurement" < > [email protected]> > Sent: Friday, December 18, 2009 9:40 PM > Subject: [time-nuts] Synchronizing to WWV > > > Hi Nuts, >> >> Most of you have probably seen this before, but I ran across a great >> 1975-vintage paper on how to synchronize your clocks and frequency >> standards >> to WWV's HF broadcasts. The equipment needs are very basic - a clock, a >> radio, and an oscilloscope. The procedure is simple and far more reliable >> than the tone-detection method I attempted earlier. >> >> NBS Technical Note 668 - The Use of National Bureau of Standards High >> Frequency Broadcasts for Time and Frequency Calibrations ( >> http://tf.nist.gov/timefreq/general/pdf/453.pdf) >> >> Yes, I realize that GPS is literally a million times more accurate, but if >> all you need is milliseconds, this will do the job cheaper than a GPSDO >> or >> it could serve as a backup. Plus it's a lot of fun to stare at the >> traces. >> They are quite hypnotic. >> >> Thanks, >> -JP >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
