Hi The power people have a tough time with RF based timing. Their equipment makes picking up anything below VHF difficult at the "point of use". Their traditional solutions were more wire line oriented. GPS was the first RF system to really get them interested. There's a FCS paper on it from the 80's(?).
Closer to the original topic. The IRIG stuff dates to 1956 according to Wikipedia. There were similar setups running around when IRIG was being worked on. The whole reason for doing it was the proliferation of incompatible gear. There must be mid 1950's gear around that did one sort of time code or another. If your definition of time code is loose enough, the electro mechanical master / slave clock could be considered a time code transmitter and receiver. That puts you back past 1900. Pretty loose definition though. Bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Hal Murray Sent: Tuesday, February 22, 2011 3:11 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Looking for info about first true radio controlled clock [email protected] said: > I'm trying to determine the first product that could automatically decode > and display a digital time code. Digital time codes were added to WWV in > 1960 and WWVB in 1965. This was before they were added to any satellite > signals, or before they were added to LF stations in Europe, such as DCF77. > Telegraphic time codes, of course, were around much earlier. Interesting question... In roughly the late 1950s, I got a tour of Niagara Mohawk's control room. That was arranged by RAGS (Radio Amateurs of Greater Syracuse). Niagara Mohawk was/is the local power company for central NY state Wikipedia says they have been borged by National Grid. http://en.wikipedia.org/wiki/Niagara_Mohawk I remember a pair of clocks (digital, I think) on the wall. I wasn't enough of a time-nut (yet) to check out the details. I'm pretty sure it was the obvious PLL, perhaps with a human in the loop. Unfortunately, I don't remember where the reference clock came from. Of course, maybe my memory is bogus. I'm pretty sure that there was something time-nut related going on. I'm petty sure that the idea of locking on to a reference clock seemed like a good one, even if I didn't know what a PLL was back then. -- These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ 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.
