Mills@UDEL.EDU (12/25/87)
Folks, A phone call to the WWV Engineer in Charge revealed that yes, they did realign the timecode generator a couple of days ago, which corresponds to the time the Heath clocks lost theirs. Happens the ancient generators (15-20 years old) had drifted from the Inter-Range Instrumentation Group (IRIG) specification, which does say "10 dB down," not "all the way down," as apparently assumed by the Heath designers. Well, the subcarrier has been misadjusted then since before I've been watching clocks, almost a decade now. Anyway, The EinC kindly offered to return the adjustment to its "original" state early next week, so our clocks might get a Christmas present after all. Turns out Precision Standard Time, Inc., is actively lobbying WWV to replace their wheezing timecode generators and there is a good possibility that might come to pass. If so, there may be a good opportunity to lobby the "advance-warning-leap-second" issue, which comes down again at the last second of the year and which will cause zillions of clocks all over the world to hiccup. Therefore, we might do well to widely publicize our outrage when, as expected, our clocks swish and sway in the first few minutes to hours after the leap. Phil Karn, I was wrong. The new transmitters have not arrived WWV yet, although they have been running at WWVH for about a year. Yes, the reason for the backwave was continuous phase tracking and yes, today's technology doesn't need that. If anybody from IRIG is alive today, punch him in the nose. Dave
louie@TRANTOR.UMD.EDU ("Louis A. Mamakos") (12/25/87)
Hey, if we're gonna insist on an advance-warning-leap-second, then we really should insist on having the YEAR be transmitted as well. Please! louie
Mills@UDEL.EDU (12/25/87)
Louie, Yes, you remember that I honk on the advance-year issue every year. I in fact raised it with the EinC, but he complained that the format is out of bits. Well, the info could be coded as a superframe, since the data rate is pretty low for that kind of stuff. Time to lobby PSTI on that, too. Ahem. Dave
andre@nrc-ut.UUCP (Andre' Hut) (01/08/88)
In article <8712241814.AA06202@trantor.UMD.EDU> louie@TRANTOR.UMD.EDU ("Louis A. Mamakos") writes: >Hey, if we're gonna insist on an advance-warning-leap-second, then we really >should insist on having the YEAR be transmitted as well. Please! Yeah! And how about a checksum too? Every once and awhile, my heathkit clock sets itself to the "correct" time, but it is several hours off. -- ----------------------------------------------------------------------------- sdcsvax-\ ihnp4-\ \ \ Andre' Hut sdcrdcf!psivax!nrcvax!nrc-ut!andre / / / hplabs--/ ucbvax!calma-/ / utah-gr!uplherc/ Network Research Corporation 923 Executive Park Dr. Suite C Salt Lake City, Utah 84117 -----------------------------------------------------------------------------
Mills@UDEL.EDU (01/24/88)
Andre', You get sixty bits, one per second in each minute, to code everything. Right now each minute is separate, but coded so you can compare one minute to the next. In principle, you don't need a checksum, since you have a built-in majority decoder capability. Heath insists that two frames (minutes) in ten be identical to achieve lock. You can do much better than this, even without changing the format, with a little imagination and spare microprocessor cycles. Dave