Well, if you're gonna be practical about it, the EMPs that take out GPS will convert a lot of silicon chips to sand. This will bring transportation to a halt - aircraft, cars, trains (at least their signaling systems), and boats (navigation if not engine controls). This could put water, food, and energy in short supply, along with manufacturing processes that rely on computers for control. Telephone and radio communication would also go away, except for the very few battery-powered vacuum tube sets.
Precision time and frequency would probably drop to last on your priority list. Have a nice day. Bill Hawkins -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of phil Sent: Tuesday, November 24, 2009 3:02 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Alternate frequency sources : DVB-T and ISDN? >> Speaking of alternate sources: Has any time-nut considered using the ISDN >> telephone network [2]? > > I think ISDN is finally dead here in Sweden. I can check if my ISDN > connection is out for good. However, I wonder if the modern replacement to > ISDN, such as ADSL is actually synchronised. It too uses OFDM/COFDM > transmission and provides pilot-tones. > >> Chris Should you have a catastrophic failure of the gps system and Loran is dead and buried, the only true source for time/frequency will be from the respective government sites. In the US it would be WWVB, WWV, NTS (internet), and acts (Telephone). I think most of you are forgetting that the bulk of the alternate sources being discussed derive their time/frequency guidance from gps. Cell towers, tv stations, tv networks, and the like will be left to their local timebases until an alternate correction scheme is developed and applied. The major tv networks "had" cesium standards, and I would think they still do but most others will be left to drift until they can be upgraded to an alternate guidance system. Another thought, if that "catastrophic" failure should take out the gps satellites, chances are it could take out the tv satellites too. Then all that's left is copper, fiber, radio, and microwave sites. If you need a reliable backup, perhaps it's time to dust off the old wwvb receivers and integrate them with these cheap rubidium standards. Perhaps now they will start bringing more than 50 bucks on epay! Phil _______________________________________________ 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.
