And with dependence on GPS we have created a serious vulnerability as too many critical pieces of infrastructure are dependent on a SINGLE precision timing and positioning system.
I can use a sextant and have a copy of Bowditch. But they only work on clear days and nights. if GPS goes down for any reason. Whats the backup solution? On Aug 10, 2018, at 2:25 PM, Lester Veenstra <[email protected]> wrote: Used to work with Wayne on two time transfer via satellite Great guy Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y [email protected] Physical and US Postal Addresses 5 Shrine Club Drive (Physical) HC84 452 Stable Ln (RFD USPS Mail) Keyser WV 26726 GPS: 39.336826 N 78.982287 W (Google) GPS: 39.33682 N 78.9823741 W (GPSDO) Telephones: Home: +1-304-289-6057 US cell +1-304-790-9192 Jamaica cell: +1-876-456-8898 -----Original Message----- From: time-nuts [mailto:[email protected]] On Behalf Of Tom Van Baak Sent: Friday, August 10, 2018 10:19 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Bicentennial GOES satellite clock Tim, Thanks for posting that photo. That space age 1976 GOES clock caught our eyes when the paper came out in 2005 (see also pages 11, 12, 13): https://tf.nist.gov/general/pdf/2013.pdf There was quite a bit of traffic on time-nuts around 2005 when the GOES satellite time service was turned off (and back on, and off, and on, and finally off for good). That left many of us with piles of 468 MHz GOES receivers, antennae, clocks and led to efforts to re-create the RF signals in-home so that GOES clocks would still work. There was even a commercial G2G (GPS to GOES) translator. Anyway, I asked around about that one-off bicentennial clock in the photo and neither the authors, NIST, or Smithsonian knows where it ended up. There's tons of information on the GOES satellite system and GOES clocks in the NIST T&F archives: https://tf.nist.gov/general/publications.htm Best to search title for GOES, or search author for Hanson. It's a fascinating glimpse into the recent past. Yes, it's sad that GOES (and Omega, and Loran-C) aren't operational anymore, but GPS does such a better job. Plus we now have cable, WiFi, cell phones, the internet, Iridium, etc. If you wanted to build your own Bicentennial GOES Clock, the design was published, including source code -- for its i4004 (!!) CPU. If you have even one minute to spare, see attached image and click on these two PDF's: "Satellite Controlled Digital Clock System (patent)" https://tf.nist.gov/general/pdf/1791.pdf "A Satellite-Controlled Digital Clock (NBS TN-681)" https://tf.nist.gov/general/pdf/452.pdf /tvb ----- Original Message ----- From: "Tim Shoppa" <[email protected]> To: "Discussion of precise time and frequency measurement" <[email protected]> Sent: Wednesday, August 08, 2018 7:29 PM Subject: [time-nuts] Bicentennial GOES satellite clock > See the groovy picture at > https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4847573/figure/f9-j110-2lom/ > > If anyone knows the whereabouts or history of the bicentennial GOES time > clock display, please let me know! > > Tim N3QE _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
