Re: [time-nuts] Bicentennial GOES satellite clock
On 8/12/18 6:36 PM, David I. Emery wrote: On Sun, Aug 12, 2018 at 07:48:52PM -0400, Bob kb8tq wrote: Hi Well???. there???s also the solar flare that vaporizes the planet earth :) A flare big enough to take out all the sat systems would disrupt a lot more than just navigation. But It is much more likely that orbits would be less accurately known for a while due to atmospheric heating and increased drag and maybe also due to disturbances in satellite orientation and power and thermal status during the event that could both change drag and perhaps even induce slight impulses if gas jets or similar means were required to recover the bird and make it stable again. And the power and thermal perturbations in emergency mode shutdown configurations might well impact the on board clock performance and accuracy (even maybe just from the extra radiation as the magnetopause moved inside the satellite orbits in an extreme event). GPS is up high enough that aerodrag isn't really a problem - if you're above 1500km, it's negligible, and they're up at 20,000km. Solar wind pressure will push them around a bit, but not much. I would think that if you did nothing, they'll be there for a very, very long time. Their orbit is actually a quite high radiation zone (traversing the radiation belts as they pass through the polar region), compared to GEO. So the GPS satellites are pretty robust to this kind of thing. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
A good sextant with a good operator can measure apparent altitude to 0.1 minutes of arc. The fastest apparent motion of objects in the sky due to rotation of the earth is 0.25 minutes of arc per second. So the best a sextant can do with time (assuming accurate astronomical tables and an exact knowledge of position) is 0.4 seconds of time. acb From: time-nuts on behalf of Dana Whitlow Sent: Sunday, August 12, 2018 4:29 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Bicentennial GOES satellite clock How exactly does one get submillisecond time of day precision with a sextant? (even if sticks and pebbles are thrown into the mix) I'd say more like ~1 sec precision on a really fine day, it the sextant is wielded by a skilled and practiced operator who has apriori knowledge of his location. And what about standard frequency dissemination? I'm also upset about the notion of time distribution and transfer by internet. Now there's a fine example of a system that could be brought down by a single competent hacker! And all it takes is one really good solar flare to bring down GPS (and Glonass and the others) semipermanently, if the reports I read are true. I argue that instead of shutting down distribution avenues, NIST should be making additional ones available. A lot has been said lately about how rapidly our technology is exploding. But think about how much of that is critically dependent on precision time transfer over the planet, and how much longer it would take mankind to recover from (insert your favorite disaster here) without good time and frequency transfer still up and working. Dana On Sun, Aug 12, 2018 at 2:06 PM, djl wrote: > all you need for a once a day noon fix is a level surface, a stick, and > some pebbles. > Don > > > On 2018-08-12 08:29, Scott McGrath wrote: > >> 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 wrote: >> >> Used to work with Wayne on two time transfer via satellite >> Great guy >> >> >> Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y >> les...@veenstras.com >> >> 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:time-nuts-boun...@lists.febo.com] 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 i4
Re: [time-nuts] Bicentennial GOES satellite clock
There have been a few television documentaries over the years on the Carrington event of 1859. https://www.history.com/news/a-perfect-solar-superstorm-the-1859-carrington-event -=Bryan=- From: time-nuts on behalf of David I. Emery Sent: August 12, 2018 6:36 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Bicentennial GOES satellite clock On Sun, Aug 12, 2018 at 07:48:52PM -0400, Bob kb8tq wrote: > Hi > > Well???. there???s also the solar flare that vaporizes the planet earth :) > > A flare big enough to take out all the sat systems would disrupt a lot more > than just navigation. > It also probably is big enough to take out HF radio gear as well. It takes a > *lot* of energy to > permanently take out a sat system. Hour or two disruptions ??? sure ??? total > destruction, that???s > getting into crazy levels. Not so clear, big events can cause satellites to fail due to large charges and voltages on induced on surfaces of the bird that cause arcs - and also bombardment by energetic particles that can cause logic states in chips to get tweaked (SEDs) and crash the control electronics and CPUS and/or confuse vital sensors.. causing the bird to enter modes that may not be safe for it or recoverable - more than a few satellites have died of these kinds of things. Whether ENOUGH GPS/Galileo/Glonnass/Baideu birds would fail to eliminate them as a functioning constellation is probably somewhat unlikely... however. But It is much more likely that orbits would be less accurately known for a while due to atmospheric heating and increased drag and maybe also due to disturbances in satellite orientation and power and thermal status during the event that could both change drag and perhaps even induce slight impulses if gas jets or similar means were required to recover the bird and make it stable again. And the power and thermal perturbations in emergency mode shutdown configurations might well impact the on board clock performance and accuracy (even maybe just from the extra radiation as the magnetopause moved inside the satellite orbits in an extreme event). So in addition to the disturbed propagation through the ionosphere causing degraded performance there well could be significant errors in ephemerides (basic bird position) that would do so too for a while. And recovering a whole constellation of confused, sick and dangerously misconfigured satellites during a massive world wide event might be less easy than one might first imagine as the resources required on the ground would probably be damaged and disabled by other effects (massive nation wide power grid collapses and the like) and would certainly be stretched thin by all the urgent problems to get under control before individual satellites started to become nearly or completely unrecoverable. And there are certainly positive feedback vicious spiral effects here - such as lack of time and position accuracy caused secondary problems such as sync failures in fiber rings and the like that might take out parts of the Internet and cell systems) and make it much harder to recover the satellites due to lack of effective communications on the ground. I'd expect that decently designed HF and LF radio time and positioning systems would be VERY much more resistant to lethal damage by flare EMPs... hard to see how massive earth magnetic events could kill LF or HF receivers that were even modestly hardened against EMP simply because otherwise local lightning would be frying them regularly. And the HF and LF transmitters involved should be pretty self protecting too... maybe their power supply would be the weak point as the grid collapsed but this is a problem that can be cheaply handled with well known and proved diesel generator technology. -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
On Sun, Aug 12, 2018 at 07:48:52PM -0400, Bob kb8tq wrote: > Hi > > Well???. there???s also the solar flare that vaporizes the planet earth :) > > A flare big enough to take out all the sat systems would disrupt a lot more > than just navigation. > It also probably is big enough to take out HF radio gear as well. It takes a > *lot* of energy to > permanently take out a sat system. Hour or two disruptions ??? sure ??? total > destruction, that???s > getting into crazy levels. Not so clear, big events can cause satellites to fail due to large charges and voltages on induced on surfaces of the bird that cause arcs - and also bombardment by energetic particles that can cause logic states in chips to get tweaked (SEDs) and crash the control electronics and CPUS and/or confuse vital sensors.. causing the bird to enter modes that may not be safe for it or recoverable - more than a few satellites have died of these kinds of things. Whether ENOUGH GPS/Galileo/Glonnass/Baideu birds would fail to eliminate them as a functioning constellation is probably somewhat unlikely... however. But It is much more likely that orbits would be less accurately known for a while due to atmospheric heating and increased drag and maybe also due to disturbances in satellite orientation and power and thermal status during the event that could both change drag and perhaps even induce slight impulses if gas jets or similar means were required to recover the bird and make it stable again. And the power and thermal perturbations in emergency mode shutdown configurations might well impact the on board clock performance and accuracy (even maybe just from the extra radiation as the magnetopause moved inside the satellite orbits in an extreme event). So in addition to the disturbed propagation through the ionosphere causing degraded performance there well could be significant errors in ephemerides (basic bird position) that would do so too for a while. And recovering a whole constellation of confused, sick and dangerously misconfigured satellites during a massive world wide event might be less easy than one might first imagine as the resources required on the ground would probably be damaged and disabled by other effects (massive nation wide power grid collapses and the like) and would certainly be stretched thin by all the urgent problems to get under control before individual satellites started to become nearly or completely unrecoverable. And there are certainly positive feedback vicious spiral effects here - such as lack of time and position accuracy caused secondary problems such as sync failures in fiber rings and the like that might take out parts of the Internet and cell systems) and make it much harder to recover the satellites due to lack of effective communications on the ground. I'd expect that decently designed HF and LF radio time and positioning systems would be VERY much more resistant to lethal damage by flare EMPs... hard to see how massive earth magnetic events could kill LF or HF receivers that were even modestly hardened against EMP simply because otherwise local lightning would be frying them regularly. And the HF and LF transmitters involved should be pretty self protecting too... maybe their power supply would be the weak point as the grid collapsed but this is a problem that can be cheaply handled with well known and proved diesel generator technology. -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
Hi Well…. there’s also the solar flare that vaporizes the planet earth :) A flare big enough to take out all the sat systems would disrupt a lot more than just navigation. It also probably is big enough to take out HF radio gear as well. It takes a *lot* of energy to permanently take out a sat system. Hour or two disruptions … sure … total destruction, that’s getting into crazy levels. Bob > On Aug 12, 2018, at 7:29 PM, Dana Whitlow wrote: > > How exactly does one get submillisecond time of day precision with a > sextant? > (even if sticks and pebbles are thrown into the mix) > I'd say more like ~1 sec precision on a really fine day, it the sextant is > wielded by > a skilled and practiced operator who has apriori knowledge of his location. > > And what about standard frequency dissemination? > > I'm also upset about the notion of time distribution and transfer by > internet. Now > there's a fine example of a system that could be brought down by a single > competent > hacker! > > And all it takes is one really good solar flare to bring down GPS (and > Glonass and > the others) semipermanently, if the reports I read are true. > > I argue that instead of shutting down distribution avenues, NIST should be > making > additional ones available. > > A lot has been said lately about how rapidly our technology is exploding. > But think > about how much of that is critically dependent on precision time transfer > over the > planet, and how much longer it would take mankind to recover from (insert > your favorite > disaster here) without good time and frequency transfer still up and > working. > > Dana > > > > > > On Sun, Aug 12, 2018 at 2:06 PM, djl wrote: > >> all you need for a once a day noon fix is a level surface, a stick, and >> some pebbles. >> Don >> >> >> On 2018-08-12 08:29, Scott McGrath wrote: >> >>> 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 wrote: >>> >>> Used to work with Wayne on two time transfer via satellite >>> Great guy >>> >>> >>> Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y >>> les...@veenstras.com >>> >>> 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:time-nuts-boun...@lists.febo.com] 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 gli
Re: [time-nuts] Bicentennial GOES satellite clock
How exactly does one get submillisecond time of day precision with a sextant? (even if sticks and pebbles are thrown into the mix) I'd say more like ~1 sec precision on a really fine day, it the sextant is wielded by a skilled and practiced operator who has apriori knowledge of his location. And what about standard frequency dissemination? I'm also upset about the notion of time distribution and transfer by internet. Now there's a fine example of a system that could be brought down by a single competent hacker! And all it takes is one really good solar flare to bring down GPS (and Glonass and the others) semipermanently, if the reports I read are true. I argue that instead of shutting down distribution avenues, NIST should be making additional ones available. A lot has been said lately about how rapidly our technology is exploding. But think about how much of that is critically dependent on precision time transfer over the planet, and how much longer it would take mankind to recover from (insert your favorite disaster here) without good time and frequency transfer still up and working. Dana On Sun, Aug 12, 2018 at 2:06 PM, djl wrote: > all you need for a once a day noon fix is a level surface, a stick, and > some pebbles. > Don > > > On 2018-08-12 08:29, Scott McGrath wrote: > >> 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 wrote: >> >> Used to work with Wayne on two time transfer via satellite >> Great guy >> >> >> Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y >> les...@veenstras.com >> >> 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:time-nuts-boun...@lists.febo.com] 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" >> To: "Discussion of precise time and frequency meas
Re: [time-nuts] Bicentennial GOES satellite clock
all you need for a once a day noon fix is a level surface, a stick, and some pebbles. Don On 2018-08-12 08:29, Scott McGrath wrote: 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 wrote: Used to work with Wayne on two time transfer via satellite Great guy Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y les...@veenstras.com 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:time-nuts-boun...@lists.febo.com] 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" To: "Discussion of precise time and frequency measurement" 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 -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. -- Dr. Don Latham PO Box 404, Frenchtown, MT, 59834 VOX: 406-626-4304 ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
Hi If GPS goes down, you then have Glonass. If Glonass goes down, you have Galileo. If all of those go down and you are in the right region, the Chinese and Japanese both have systems you could use. In terms of *system* failure, there’s a lot of redundancy out there ….. Yes, you *would* have to own gear that works with all those systems. You might also go with multi-band (quad band maybe) gear to eliminate various other issues. Widely deployed electronic navigation isn’t all that old. People got along for a really long time without it ….. That includes a whole bunch of folks who had no clue how a sextant works. Bob > On Aug 12, 2018, at 10:29 AM, Scott McGrath wrote: > > 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 wrote: > > Used to work with Wayne on two time transfer via satellite > Great guy > > > Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y > les...@veenstras.com > > 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:time-nuts-boun...@lists.febo.com] 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" > To: "Discussion of precise time and frequency measurement" > > 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 -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > ___ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
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 wrote: Used to work with Wayne on two time transfer via satellite Great guy Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y les...@veenstras.com 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:time-nuts-boun...@lists.febo.com] 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" To: "Discussion of precise time and frequency measurement" 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 -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there. ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
Used to work with Wayne on two time transfer via satellite Great guy Lester B Veenstra K1YCM MØYCM W8YCM 6Y6Y les...@veenstras.com 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:time-nuts-boun...@lists.febo.com] 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" To: "Discussion of precise time and frequency measurement" 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 -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
yes I still have a modified 468 that works using some stuff I design back in 2005. I do power the dc468 up every now and then. Still works. Though a couple of the panaplex displays are getting a bit cranky. But completely agree that GPS has seriously spoiled me as it drives time code clocks. Regards Paul WB8TSL On Fri, Aug 10, 2018 at 10:18 AM, Tom Van Baak wrote: > 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" > To: "Discussion of precise time and frequency measurement" < > time-nuts@lists.febo.com> > 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 -- time-nuts@lists.febo.com > To unsubscribe, go to http://lists.febo.com/mailman/ > listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
Re: [time-nuts] Bicentennial GOES satellite clock
Tom, thank you for those links! Yes, my employer used successive generations of GOES satellite clock receivers that generated IRIG signals piped around the company. Even though my company started in revenue service in 1976 I don't think we had our first GOES clock until a few years later. The IRIG signals were not just used for internal displays. In the 1980's each passenger station got public facing LED clocks that were standard NatSemi LED display chips but "force synchronized" at top of each hour and at midnight via audio tones driving relay contacts that stimulated the set pushbutton inputs of the NatSemi chips. When GOES was turned off in 2004, then we switched to NTP controlled IRIG generator and only in the past month have we removed the last internal IRIG clock displays. All the passenger facing LED clocks had been removed in the past decade too. I am building a miniature reproduction of the bicentennial clock although it will obviously not be run through GOES or use a 4004. Current prototype uses a ESP8266 and NTP over WiFi. Tim N3QE On Fri, Aug 10, 2018 at 10:18 AM, Tom Van Baak wrote: > 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" > To: "Discussion of precise time and frequency measurement" < > time-nuts@lists.febo.com> > 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 -- time-nuts@lists.febo.com > To unsubscribe, go to http://lists.febo.com/mailman/ > listinfo/time-nuts_lists.febo.com > and follow the instructions there. > > ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
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" To: "Discussion of precise time and frequency measurement" 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 -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
