I have Arduino and Parallax BS2 programs that check the time from a Motorola GPS card (UT) and then send out a pulse on an electronic relay once an hour. The pulse starts at 59:57 past the hour and ends at 59:59. The solenoid releases on each clock pretty close to the hour, and the clocks remain in synch indefinitely. The time is also displayed on a 2 line LCD in the GPS interface module. I've had this working in my house for years now, starting with WWV, WWVB, and now GPS. I'm happy to send the program to anyone interested. I've also used to drive slave clocks with a 1PPM pulse. Currently I have over 25 Self Winding clocks all synchronized. I have them wired serially in groups of 4 and send out 12v to each group. Works great.
Mitch. -----Original Message----- From: time-nuts [mailto:[email protected]] On Behalf Of [email protected] Sent: Saturday, November 01, 2014 5:51 AM To: [email protected] Subject: time-nuts Digest, Vol 124, Issue 2 Send time-nuts mailing list submissions to [email protected] To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to [email protected] You can reach the person managing the list at [email protected] When replying, please edit your Subject line so it is more specific than "Re: Contents of time-nuts digest..." Today's Topics: 1. HP Z3816A GPS ([email protected]) 2. Re: 10MHz Rubidium reference source for frequency counter (John Miles) 3. Re: Setting Clocks in the Mid 1800's (Sanjeev Gupta) 4. Re: Mercury Ion Clock (Poul-Henning Kamp) 5. Selling time to the railroad (Howard Davidson) 6. Re: Mercury Ion Clock (Magnus Danielson) 7. Re: Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system (Mike Seguin) 8. Re: 1903 Railroad self-Winding / Self-setting Clock (Bob Camp) ---------------------------------------------------------------------- Message: 1 Date: Sat, 1 Nov 2014 02:15:52 -0400 From: [email protected] To: [email protected] Subject: [time-nuts] HP Z3816A GPS Message-ID: <[email protected]> Content-Type: text/plain; charset="US-ASCII" Hello All... My HP Z3816A GPS box is in need of some TLC. Is there anyone on the list who works on these units? TIA 73 Don W4WJ ------------------------------ Message: 2 Date: Sat, 1 Nov 2014 00:01:19 -0700 From: "John Miles" <[email protected]> To: "'Discussion of precise time and frequency measurement'" <[email protected]> Subject: Re: [time-nuts] 10MHz Rubidium reference source for frequency counter Message-ID: <[email protected]> Content-Type: text/plain; charset="utf-8" > >It seems to me that it's just a case of expecting too much from a counter. > > Possibly, but a well-tuned 5370B can get to the low e-12's at 1-10 > seconds. You can get down there with TI averaging, but the data you get is not ideal since the averaging process smooths out the very instabilities you're trying to characterize. (See Tom's page at http://www.leapsecond.com/pages/adev-avg/ for a good intuitive explanation.) > Yes, using TI mode is essential for getting down to the counter's > limits. Was Karen using frequency mode? I wasn't paying attention to > that end of things. I'm not sure, but that's where most people start out. Going to TI mode may improve things a bit at the cost of a more complex, error-prone measurement process, but it still isn't going to measure a Morion at t=1s. -- john, KE5FX Miles Design LLC ------------------------------ Message: 3 Date: Sat, 1 Nov 2014 15:14:51 +0800 From: Sanjeev Gupta <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]> Subject: Re: [time-nuts] Setting Clocks in the Mid 1800's Message-ID: <cahzk5wdzpkrhgm1vswvpms-rwfwq0crfz_lxzrwxtgty5ok...@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 On Sat, Nov 1, 2014 at 11:23 AM, Larry McDavid <[email protected]> wrote: > I gave a presentation on the Dent Dipleidoscope at the Harvard > conference of the North American Sundial Society in 2013. If anyone is > interested, I can provide a pdf of that presentation. The presentation > includes history, detailed explanation of operation and lots of > pictures of the construction of the dipleidoscope. (specifically on-list) Larry, I, for one, would appreciate your presentation. -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane ------------------------------ Message: 4 Date: Sat, 01 Nov 2014 07:21:51 +0000 From: "Poul-Henning Kamp" <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]>, Brooke Clarke <[email protected]> Subject: Re: [time-nuts] Mercury Ion Clock Message-ID: <[email protected]> Content-Type: text/plain; charset="us-ascii" -------- In message <[email protected]>, Brooke Clarke writes: >Hi Bob: > >I suspect that inside a screen room like that one, where I'm >guessing the walls are iron/steel, there's not much of the >Earth's mag field left to null. That would be very counter productive, because you would invariably get a very complex mag field which owuld be much harder to cancel out. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [email protected] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ------------------------------ Message: 5 Date: Sat, 01 Nov 2014 00:29:20 -0700 From: Howard Davidson <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]> Subject: [time-nuts] Selling time to the railroad Message-ID: <[email protected]> Content-Type: text/plain; charset=iso-8859-15; format=flowed The physics department at the little Liberal Arts college I went to in Iowa, Grinnell college, used to sell time to the Rock Island Railroad. We had two excellent pendulum clocks that back when this was in action, were synchronized to zenith crossings of particular stars. This was a manual operation performed by undergraduates who were paid to be up at weird hours of the night. The time ticks from the clocks were transmitted to the Rock Island station in town electrically. I presume they distributed it by telegraph. hld -- Howard L. Davidson [email protected] ------------------------------ Message: 6 Date: Sat, 01 Nov 2014 11:42:59 +0100 From: Magnus Danielson <[email protected]> To: [email protected] Cc: [email protected] Subject: Re: [time-nuts] Mercury Ion Clock Message-ID: <[email protected]> Content-Type: text/plain; charset=utf-8; format=flowed Hi Bob, The traditional Hg ion clock with it's 40,5 GHz frequency is doable, but it would be interesting if it could be commercialized at a (time-nuts) friendly price. The modern optical clock got much easier to work with when the frequency comb was invented. The frequency comb and stable lasers is now commercialized, but not cheap, not cheap at all. Cheers, Magnus On 11/01/2014 02:27 AM, Bob Camp wrote: > Hi > > Trapped ion clocks have been the “obvious successor” to a Cs tube for at > least 30 years. There is a *lot* of very fancy work involved in getting from > 10 MHz up to a very specific light wavelength with low ADEV and good phase > noise….. > > Rocket science indeed. Time Nuts rocket science, but tough to do none the > less. > > Bob > >> On Oct 31, 2014, at 8:09 PM, paul swed <[email protected]> wrote: >> >> Humor aside. I did dig deeper. It seems that this technology could be >> commercialized in larger volumes and might land in the same cost as a good >> CS does today. Technically it looks reasonable. >> Regards >> Paul >> WB8TSL >> >> On Fri, Oct 31, 2014 at 1:45 PM, paul swed <[email protected]> wrote: >> >>> Jim >>> I am sorry to say thats the wrong clock picture. >>> That picture is of 2 glass coffee tables and a toaster in between. >>> I see you can order that art om ebay. Item number 142657nottoday3245 >>> Regards >>> Paul >>> WB8TSL >>> >>> On Fri, Oct 31, 2014 at 1:36 PM, Jim Lux <[email protected]> wrote: >>> >>>> OK, I know you all want to go get one... >>>> >>>> http://discoverjpl.jpl.nasa.gov/posts/520 >>>> >>>> It's Bob Tjoelker in front of the Deep Space Atomic Clock (DSAC) being >>>> tested for magnetic field sensitivity. It's a trapped ion clock, 1 liter/1 >>>> kg, orders and orders of magnitude better than a USO in performance. >>>> >>>> (if it's in the building I think it's in, the rebar is made of >>>> non-magnetic stainless steel) >>>> _______________________________________________ >>>> 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. > > _______________________________________________ > 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. > ------------------------------ Message: 7 Date: Sat, 01 Nov 2014 07:42:30 -0400 From: Mike Seguin <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]> Subject: Re: [time-nuts] Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812A GPSDO system Message-ID: <[email protected]> Content-Type: text/plain; charset=utf-8; format=flowed Hi Arthur, Found your original picture/post. TNX! http://s906.photobucket.com/user/rjb1998/media/RFTG-uREF1photo1_zps87c505ca.jpg.html Would you share what you did for a 5 MHz buffer? Mike On 10/31/2014 10:20 PM, Arthur Dent wrote: > Bob Stewart bob at evoria.net > “…I have both of my units sitting on the bench. I found that I needed to > connect them together to get the REF1 unit to come out of standby….” > > Bob Camp kb8tq at n1k.org > “I suspect that somebody will have to figure out what the 15 pin > connector / jumper is doing. On previous RFTG units there was a > way to re-wire the crossover interface to fake out the slave detect > process. That would let you run a single GPS equipped box and have > it behave correctly. Without the fake wires trick none of them > played nice without the slave being present….” > ++++++++++++++++++++++++++++++++++++++ > Reposting what I had posted over a week ago, in case you missed it…. > > Arthur Dent golgarfrincham at gmail.com Wed Oct 22 13:59:48 EDT 2014 > “…Way back on Fri Jun 11 16:48:43 UTC 2010 I posted about using one of > these units I had modified but at the time there wasn't a single person > who was interested. I have been using the RFTG-u REF1 since then and > it is a nice unit. The modifications I added (including a power supply > -see photo) allows the lights to cycle through their normal sequence > on warm-up and the second unit isn't needed at all….” > > -Arthur > _______________________________________________ > 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. > -- 73, Mike, N1JEZ "A closed mouth gathers no feet" ------------------------------ Message: 8 Date: Sat, 1 Nov 2014 08:50:26 -0400 From: Bob Camp <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]> Subject: Re: [time-nuts] 1903 Railroad self-Winding / Self-setting Clock Message-ID: <[email protected]> Content-Type: text/plain; charset=utf-8 Hi The “easy way” is probably to take a GPS module and get the time out of that. There’s not a big need for a GPSDO in this case. The modules cost < $20 and run on very little power. Mate the module up with your processor du-jour and let it figure out when the top of the hour is. There are a *bunch* of < $15 boards out there. No need for anything fancy. The advantage of having a bit of code is that it can *know* when you are at 12:00:00 rather than having to count 3600 seconds past the last reset. I would use a … relay… to drive the clock. That way everything is isolated from everything else. You also get a nice real sounding click when it fires. Total cost of everything < $50. Total time to get it all done….. I would take the clock to a “clock guy” to make sure it’s up to running this way. It would be a shame to fire things up and find that there is a problem with the clock. Even worse if you break something in the clock. ————————————————— Totally off topic … we had a similar system in 8th grade. For some odd reason the reset didn’t work quite right. The clock tended to go nuts when the reset signal came through. Very distracting …. wonder why it did that …. Bob > On Oct 31, 2014, at 9:29 PM, Mike Baker <[email protected]> wrote: > > Hello, Time-Nutters-- > > A friend has a vintage oak-cabinet pendulum movement > clock made by The Self Winding Clock Company some time > around 1903. The company was formed in 1886. By the > early 1900's era, this clock was known for its relative > accuracy. These clocks were pendulum controlled and > powered by a rather small and frequently reset > mainspring that was wound hourly by a set of 1.5 VDC > dry-cell batteries. In 1890 (?) the Naval Observatory agreed > to telegraph standard railway time. Western Union, > which also owned the Self-Winding Clock Company, sold > these clocks to the railroads and sent the hourly time > coordinating signals around the country by telegraph. > My friend has one of the railroad clocks that has the > Western Union Telegraph hourly resetting option. > > My friend thought it would be an interesting juxtaposition > of technology from two different eras by creating the > momentary 3-volt resetting pulse every hour from a > GPS disciplined oscillator / clock pulse. > > I am wondering what the easiest approach to this might > be? I suppose I could take the 1-sec pulses from a > GPSDO (Trimble Thunderbolt ?) and count 3600 of them > to generate a momentary reset 3VDC signal. In any event, > I thought I would pass this by the Time-Nuts gang to see > if any feedback is available as to what the least complicated > (simplest) way might be to accomplish this. > > Mike Baker > *************** > > > _______________________________________________ > 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. ------------------------------ Subject: Digest Footer _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ------------------------------ End of time-nuts Digest, Vol 124, Issue 2 ***************************************** _______________________________________________ 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.
