Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
and that magic timing machine was the vibrograph, more abot it here: https://www.google.com/search?q=vibrographclient=firefox-ahs=Kyhrls=org.mozilla:en-US:officialchannel=nptbm=ischtbo=usource=univsa=Xei=iK6RVeX4FJTUoASf2KeIBQved=0CB4QsAQbiw=1024bih=507 we had one 73 KJ6UHN On 6/29/2015 12:16 PM, Chuck Harris wrote: Back in the day when mechanical escapement pocket watches, and wrist watches were state of the art, the jeweler would adjust the watch to run at a normal rate, and give them a daily wind. Everything looked nice in the display case. When a customer bought a watch, the jeweler would set the watch to his shop clock, and instruct the customer to wear, and wind the watch normally for two weeks, but do not set it. At the end of the two weeks, bring the watch back to the shop for a check up... When the watch came back, the jeweler would calculate the number of days the watch had been worn, note the difference from his shop clock, and calculate the daily rate of the watch. He would then set his timing machine for the the inverse of that rate, and set the watch to match. Now, when the customer wore his watch, the watch would seem to always be right on because it was adjusted for a rate that compensated for the customer's patterns of wearing the watch...his personal error. This trick had an added advantage because the customer got to see how so-so his brand new watch behaved during those two weeks, and got to be dazzled by his jeweler's rare ability to make the new watch perform so much better than the factory could! If this was normal back at the turn of the 20th century, why wouldn't Casio, and others at least do as well? Especially now that all electronic watches have a microprocessor built in... complete with temperature sensing diodes, battery monitors, and other nifty gadgets. -Chuck Harris Bryan _ wrote: But wouldn't normal watch wear just balance itself over time, one wears their watch for say 12 hours and the rest it sits on a counter at a much colder temperature. So wonder if Casio would actually go to such lengths to compensate. Maybe, interesting though. -=Bryan=- ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Large clock display from NMEA input? (Should understand leap second).
NMEA is just ASCII text. You can read the output in terminal window. Every second the GPS will send a set of sentences. On Mon, Jun 29, 2015 at 7:57 PM, Dave Martindale dave.martind...@gmail.com wrote: Tomorrow evening, I'm going to a leap second barbecue. The barbecue itself was the idea of a friend, but I'm bringing the equipment to show the leap second. My main setup is a Thunderbolt, Lady Heather running on a PC laptop, and a serial to USB converter. It's all working sitting here on a desk this evening, so the only thing I can't test in advance is the leap second itself. I haven't had the Thunderbolt running during a leap second before, but there is a YouTube video showing the June 2012 leap second as handled by a Thunderbolt and Lady Heather, so I'm assuming all will work as expected. Never one to trust a single piece of hardware completely, I want to bring a backup. I have an old Garmin GPS-25 board mounted in a box with power supply and RS-232 level converters, so I want to bring it too. I have watched a leap second previously on the GPS-25, so I know it handles the event properly. But the GPS-25 is NMEA output so it won't work with Lady Heather. I need something else to display a digital clock that everyone can see, from a NMEA data stream. VisualGPS displays a bunch of interesting stuff, but not time. U-center from u-blox displays UTC as both analog and digital clock, and the analog clock can be made as large as you have screen space for. Does anyone know what it does with a leap second? Are there other programs I should look at? - Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
Hi Well there are a few possibilities: 1) The person wears their watch 24 hours a day 2) They take it off for random periods of time 3) The person swims marathons weekly in cold water with their watch on 4) The watch sites in a cabinet for 10 years The further down that list the colder the watch runs. Cassio and pretty much everybody else *do* temperature compensate their watches for the nominal temperature characteristic of the crystal they use. It is easy to do digitally and thus costs nothing (either in silicon area or power). They also adjust the watch on frequency digitally rather than mechanically. Compared to the way we used to do it (40 years ago), it’s a lot cheaper to do it the “new way”. It is interesting that the nominal set point is still “fast” though. Bob On Jun 29, 2015, at 2:42 AM, Bryan _ bpl...@outlook.com wrote: But wouldn't normal watch wear just balance itself over time, one wears their watch for say 12 hours and the rest it sits on a counter at a much colder temperature. So wonder if Casio would actually go to such lengths to compensate. Maybe, interesting though. -=Bryan=- From: kb...@n1k.org Date: Sun, 28 Jun 2015 20:41:15 -0400 To: time-nuts@febo.com Subject: Re: [time-nuts] Casio Watches 13 Year Drift in Seattle Hi Just to clarify: In the “art” the watches all ran fast rather than slow. They *would* have run slow if the room temperature / skin temperature delta was an issue. Since they did not, one assumes that Casio digitally compensates this model (and probably all their watches). The typical watch tuning fork will shift more than the observed delta when run in a cold court house if un-compensated. By far the best explanation is the “set to deliberately run fast” one. Bob On Jun 27, 2015, at 8:19 PM, Jim Palfreyman jim77...@gmail.com wrote: My Casio g shock keeps extraordinary time. I did open it up and tune it, but still I'd expect it to drift. After 6 months untouched I still can't separate by eye the second from UTC. Also, with regard to the video's query about all the clocks running slow - they have been tuned to run at the temperature of a person's wrist. On Sunday, 28 June 2015, John Stuart j.w.stu...@comcast.net wrote: I think there may be a new Time-Nut in the Seattle area, , , Art, Engineering and Justice - how accurate is a Casio watch? https://www.youtube.com/watch?v=hwOMUhS8gV0 John, KM6QX ___ time-nuts mailing list -- time-nuts@febo.com javascript:; To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Casio Watches 13 Year Drift in Seattle
A friend of mine is the test engineer/clock guru for one of the major manufacturers of clock chips. Rest assured that all watch makers know the usage profiles for their customers quite well and they do indeed tweak the chip to compensate for the typical profile. If your usage pattern does not match that of the masses, your accuracy can suffer. Also, you cant assume that all clock circuits will run faster or slower with rising/falling temperature changes. Some circuits run faster with rising temperatures, others will run slower. A very big concern in the clock chip world these days is getting the clock/crystal to start/run reliably with the ever decreasing power requirements of the customers. A clock chip oscillator these days draws in the low nanoamp area, and they can be very sensitive to things like electrical noise (beware of the dreaded stepper noise), board layout, IC process variations, etc. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
If this was normal back at the turn of the 20th century, why wouldn't Casio, and others at least do as well? Especially now that all electronic watches have a microprocessor built in... complete with temperature sensing diodes, battery monitors, and other nifty gadgets. I am guessing the vast majority of Casio owners don't especially care if their watch gains or loses a minute every month. So why bother to add sensors and circuitry to compensate for its environment? Furthermore, it requires setting the initial frequency on each watch built, to compensate for the crystal's initial error. And that jacks up the cost, perhaps more than adding those sensors would. Better to just churn them out with as little per-unit testing as possible. That's just my guess ... but who am I to say? Regards, Andy ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Greetings from Australia
Hi Guys :) I thought I’d say thanks for the add to the group and introduce myself. [] I have a question… Is the reason most amateur radio people care about accurate frequency mostly about operating at higher radio frequencies? I imagine if a bunch of radio enthusiasts aligned their HF radios with atomic standards for use on those bands that doppler shift would ruin everything the additional hardware put into it. Cheers, Brek. = Welcome, Brek! It isn't just frequency, but time as well. There are some modes where the time needs to be known to within about 1/10 second, which can be easily achieved running NTP on Windows PCs. Having a local GPS-locked stratum-1 server based on a PC (Windows or Linux) or Raspberry Pi makes this independent of needing an Internet connection - e.g. for field work. Cheers, David -- SatSignal Software - Quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Reeeely long term HP 5065A drift rate (13 year!)
Did you take into account difference in height (if it was significantly different)? Hi Jim, Two things about altitude and clocks. First, the unit was calibrated by Corby 13 years ago and again now. Presumably same house; same altitude. So there is no net before-vs-after height difference to cause some kind of relativistic effect. And second, even if you took the gravitational effect on atomic clock frequency into consideration, it's still only about 1e-16/m or 1e-13/km. So if you lived in Boulder, CO (~ 5400 feet) the effect is just 1.8e-13. His measurement of ~2e-11 is still a hundred times greater than a relativistic effect. And of course, as soon as you ship the clock back to Corby near sea level, it goes back to its normal rate. So it doesn't matter if the 5065A lived 13 years at sea level or on a mountain or in a deep well or was installed in the space station. The key is that it was recently recalibrated at the same location it was originally calibrated. Make sense? /tvb ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] End Of The World
Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? Bob ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Help with my ADEV measurement setup
I tried both the PPS and the 10MHz signal on channel 1, with the 10MHz DUT on channel 2. Tom emailed me and it turns out the software was not detecting the units correctly from the serial string. (What are 6 powers of ten between friends, right? :) ) Likely a settings mistake on my part, I sent him a screen cap to see what's up. None the less, I manually enter the time units and was able to plot some data. I attached a new screen cap. How does this look? Thanks Dan On Tue, Jun 30, 2015 at 5:36 PM, Bob Camp kb...@n1k.org wrote: Hi Are you using a PPS as the “start” and the 10 MHz as the “stop” or comparing two PPS signals? Bob On Jun 30, 2015, at 2:47 PM, Dan Watson watsondani...@gmail.com wrote: Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup: - 53131A with the OCXO option. Calibrated against a T-bolt. I also did the TI Quik cal and it passed - I'm using RS-232 out with a null modem cable into a Serial-USB converter - Software is TimeLab in talk-only mode. 53131A check box is checked. - The counter is in TI mode, with a T-bolt on Channel 1 and DUT on Channel 2 - A delay of 1 second is set on the counter. TimeLab seems to accurately detect this interval I started measuring various devices, and could never seem to get better than around 1x10^-6. Even my Rb was showing a 1 second ADEV of 10^-6. Finally I put the T-bolt on channel 1 with common mode on to both channels, and it still measures around 10^-6. A picture of that is attached. Surely this can't be right. I tried frequency mode and it gives ADEVs of 10^-12 on the Rb and T-bolt, as expected. I understand the issues with filtering that the 53131A does internally on this mode, but at least it shows my setup is working to some degree. It's TI mode that seems to be wonky. I'm probably doing something really stupid. Thanks for any help you all can suggest. Regards, Dan W adevtest.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Leap second results: WWVB
My linux parallel port WWVB 'scope got a bit confused at the leap second: Tue Jun 30 23:58:59 2015 | | X Tue Jun 30 23:59:00 2015 | | X Tue Jun 30 23:59:01 2015 | - | 1 Tue Jun 30 23:59:02 2015 | -- | 0 Tue Jun 30 23:59:03 2015 | - | 1 Tue Jun 30 23:59:04 2015 | -- | 0 Tue Jun 30 23:59:05 2015 | - | 1 Tue Jun 30 23:59:06 2015 | -- | 0 Tue Jun 30 23:59:07 2015 | -- | 0 Tue Jun 30 23:59:08 2015 | - | 1 Tue Jun 30 23:59:09 2015 | ---| X Tue Jun 30 23:59:10 2015 | ---| 0 Tue Jun 30 23:59:11 2015 | ---| 0 Tue Jun 30 23:59:12 2015 | - | 1 Tue Jun 30 23:59:13 2015 | -- | 0 Tue Jun 30 23:59:14 2015 | -- | 0 Tue Jun 30 23:59:15 2015 | -- | 0 Tue Jun 30 23:59:16 2015 | -- | 0 Tue Jun 30 23:59:17 2015 | - | 1 Tue Jun 30 23:59:18 2015 | - | 1 Tue Jun 30 23:59:19 2015 | ---| X Tue Jun 30 23:59:20 2015 | --| 0 Tue Jun 30 23:59:21 2015 | ---| 0 Tue Jun 30 23:59:22 2015 | -- | 0 Tue Jun 30 23:59:23 2015 | - | 1 Tue Jun 30 23:59:24 2015 | -- | 0 Tue Jun 30 23:59:25 2015 | - | 1 Tue Jun 30 23:59:26 2015 | ---| 0 Tue Jun 30 23:59:27 2015 | ---| 0 Tue Jun 30 23:59:28 2015 | -- | 0 Tue Jun 30 23:59:29 2015 | | X Tue Jun 30 23:59:30 2015 | --| 0 Tue Jun 30 23:59:31 2015 | -- | 0 Tue Jun 30 23:59:32 2015 | ---| 0 Tue Jun 30 23:59:33 2015 | - | 1 Tue Jun 30 23:59:34 2015 | ---| 0 Tue Jun 30 23:59:35 2015 | ---| 0 Tue Jun 30 23:59:36 2015 | --| 0 Tue Jun 30 23:59:37 2015 | | 1 Tue Jun 30 23:59:38 2015 | --| 0 Tue Jun 30 23:59:39 2015 | --| X Tue Jun 30 23:59:40 2015 | ---| 0 Tue Jun 30 23:59:41 2015 | - | 1 Tue Jun 30 23:59:42 2015 | - | 1 Tue Jun 30 23:59:43 2015 | - | 1 Tue Jun 30 23:59:44 2015 | -- | 0 Tue Jun 30 23:59:45 2015 | - | 0 Tue Jun 30 23:59:46 2015 | -- | 0 Tue Jun 30 23:59:47 2015 | --| 0 Tue Jun 30 23:59:48 2015 | - | 1 Tue Jun 30 23:59:49 2015 | | X Tue Jun 30 23:59:50 2015 | -- | 0 Tue Jun 30 23:59:51 2015 | - | 1 Tue Jun 30 23:59:52 2015 | -- | 0 Tue Jun 30 23:59:53 2015 | - | 1 Tue Jun 30 23:59:54 2015 | -- | 0 Tue Jun 30 23:59:55 2015 | -- | 0 Tue Jun 30 23:59:56 2015 | | 1 Tue Jun 30 23:59:57 2015 | - | 1 Tue Jun 30 23:59:58 2015 | - | 1 Tue Jun 30 23:59:59 2015 | | X Wed Jul 1 00:00:00 2015 | | X Wed Jul 1 00:00:00 2015
[time-nuts] Leap second results: LH screenshot
The /nd=1sr command made this capture a piece of cake: http://www.n5tnl.com/time/leap_2015/tbolt_leap.gif ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Leap second results: WWVB
Hi Scott, That's a nice WWVB result. Yes, the triple marker pulse looks is correct for a positive leap second. What did you use for a receiver? My efforts were modest this year. iPhone screen capture of time.gov using pacific daylight time instead of the usual UTC: http://leapsecond.com/images/2015-leapsecond-time-gov.png Nixie leap second clock (designed to be right once every few years): http://leapsecond.com/images/CD47-235960.jpg /tvb - Original Message - From: Scott Newell newell+timen...@n5tnl.com To: time-nuts@febo.com Sent: Tuesday, June 30, 2015 5:24 PM Subject: [time-nuts] Leap second results: WWVB My linux parallel port WWVB 'scope got a bit confused at the leap second: ... Tue Jun 30 23:59:57 2015 | - | 1 Tue Jun 30 23:59:58 2015 | - | 1 Tue Jun 30 23:59:59 2015 | | X Wed Jul 1 00:00:00 2015 | | X Wed Jul 1 00:00:00 2015 | | X Wed Jul 1 00:00:01 2015 | ---| 0 Wed Jul 1 00:00:02 2015 | -- | 0 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Help with my ADEV measurement setup
Hi Your OCXO and the TBolt *should* be down around 1x10^-11 to 1x10^-12 at one second. That’s a factor of 10 to 100X better than the 53131 can do at a random frequency. At exactly 10 MHz it may be even worse than that. Effectively what you will be doing is measuring the noise floor of the counter out to a few hundred seconds. To get useful data, plan on runs of at least several hours, if not a few days. Bob On Jun 30, 2015, at 8:05 PM, Dan Watson watsondani...@gmail.com wrote: I tried both the PPS and the 10MHz signal on channel 1, with the 10MHz DUT on channel 2. Tom emailed me and it turns out the software was not detecting the units correctly from the serial string. (What are 6 powers of ten between friends, right? :) ) Likely a settings mistake on my part, I sent him a screen cap to see what's up. None the less, I manually enter the time units and was able to plot some data. I attached a new screen cap. How does this look? Thanks Dan On Tue, Jun 30, 2015 at 5:36 PM, Bob Camp kb...@n1k.org wrote: Hi Are you using a PPS as the “start” and the 10 MHz as the “stop” or comparing two PPS signals? Bob On Jun 30, 2015, at 2:47 PM, Dan Watson watsondani...@gmail.com wrote: Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup: - 53131A with the OCXO option. Calibrated against a T-bolt. I also did the TI Quik cal and it passed - I'm using RS-232 out with a null modem cable into a Serial-USB converter - Software is TimeLab in talk-only mode. 53131A check box is checked. - The counter is in TI mode, with a T-bolt on Channel 1 and DUT on Channel 2 - A delay of 1 second is set on the counter. TimeLab seems to accurately detect this interval I started measuring various devices, and could never seem to get better than around 1x10^-6. Even my Rb was showing a 1 second ADEV of 10^-6. Finally I put the T-bolt on channel 1 with common mode on to both channels, and it still measures around 10^-6. A picture of that is attached. Surely this can't be right. I tried frequency mode and it gives ADEVs of 10^-12 on the Rb and T-bolt, as expected. I understand the issues with filtering that the 53131A does internally on this mode, but at least it shows my setup is working to some degree. It's TI mode that seems to be wonky. I'm probably doing something really stupid. Thanks for any help you all can suggest. Regards, Dan W adevtest.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. adevplot_PPS.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Reeeely long term HP 5065A drift rate (13 year!)
Hi Corby -- it just so happens that I've been plotting my 5065A (super) against several sources since last February -- about 130 days of data so far. Here's the data against a GPSDO as reference: http://febo.com/pages/plots/chronos/hp5065a-z3805a.html This is based on PPS comparisons. John On Jun 30, 2015, at 1:21 PM, cdel...@juno.com cdel...@juno.com wrote: Yes, same workbench and location! How about some of the 5065A owners helping out in a bigger sample? What I thought is that say on July the 4th a few owners measure their frequency offset to say at least 5X10-12th and then without changing the C-field for a year we could repeat the measurement next year and see what kind of results we get. Units would not have to stay powered on the entire time as long a you give them a day or so to warm up before the measurements. The Independence day 5065A offset club! Cheers, Corby ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Help with my ADEV measurement setup
Let's see a snapshot of your acquisition dialog, just before you hit 'Start'. (Or send me a .tim file directly.) It can be tricky to configure the test setup for a TI measurement, since so many more things can go wrong compared to a frequency-based setup. -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Watson Sent: Tuesday, June 30, 2015 11:48 AM To: time-nuts@febo.com Subject: [time-nuts] Help with my ADEV measurement setup Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Help with my ADEV measurement setup
Attached is a screenshot of the setup window. I manually typed in 1E-6 as the units. I also hit Monitor and let it average the reporting interval for a while until it settled at 1.00 seconds. Originally I was leaving the time unit as 1, and microseconds in in the serial string was not being detected to set the units automatically. I'd be happy to send you a tim file as well if necessary. Let me know. Thanks Dan On Tue, Jun 30, 2015 at 8:51 PM, John Miles j...@miles.io wrote: Let's see a snapshot of your acquisition dialog, just before you hit 'Start'. (Or send me a .tim file directly.) It can be tricky to configure the test setup for a TI measurement, since so many more things can go wrong compared to a frequency-based setup. -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Watson Sent: Tuesday, June 30, 2015 11:48 AM To: time-nuts@febo.com Subject: [time-nuts] Help with my ADEV measurement setup Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup... ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Help with my ADEV measurement setup
Yep, it will ignore any non-numeric data like us suffixes. It will always interpret incoming data as seconds, so the 1E-6 scale factor is appropriate if the counter is returning microseconds. I'll tweak the mouseover help text for the scale factor field to clarify that. I think you're basically getting valid data. The 53131A's one-shot resolution is 0.5 ns, and you're seeing about 2E-9 residual ADEV at t=1s. It's in the right ballpark, anyway... e.g., on a 20-ps HP 5370, the residual ADEV at t=1s will usually be in the neighborhood of 30-60 ps. I would, however, be worried about aliasing with a TCXO. If its frequency is more than 5E-8 off -- meaning it drifts more than 50 nanoseconds per second with 10 MHz at the STOP jack -- its error will end up underrepresented in the measurement. In this case your oscillator is drifting quite a bit (as expected) -- look at the 'w' view of the original phase compared to the unwrapped 'p' phase. You could try putting 1pps on both the START and STOP jacks but that'll require more futzing with scale factors, 1pps dividers and the like, and may leave you more vulnerable to trigger uncertainty from various causes. For measurement of a TCXO, I'd stick with frequency mode. The ADEV plots won't be 100% kosher but they'll be fine for relative comparisons with other plots from the same measurement setup. -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Watson Sent: Tuesday, June 30, 2015 5:05 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Help with my ADEV measurement setup I tried both the PPS and the 10MHz signal on channel 1, with the 10MHz DUT on channel 2. Tom emailed me and it turns out the software was not detecting the units correctly from the serial string. (What are 6 powers of ten between friends, right? :) ) Likely a settings mistake on my part, I sent him a screen cap to see what's up. None the less, I manually enter the time units and was able to plot some data. I attached a new screen cap. How does this look? Thanks Dan On Tue, Jun 30, 2015 at 5:36 PM, Bob Camp kb...@n1k.org wrote: Hi Are you using a PPS as the “start” and the 10 MHz as the “stop” or comparing two PPS signals? Bob On Jun 30, 2015, at 2:47 PM, Dan Watson watsondani...@gmail.com wrote: Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup: - 53131A with the OCXO option. Calibrated against a T-bolt. I also did the TI Quik cal and it passed - I'm using RS-232 out with a null modem cable into a Serial-USB converter - Software is TimeLab in talk-only mode. 53131A check box is checked. - The counter is in TI mode, with a T-bolt on Channel 1 and DUT on Channel 2 - A delay of 1 second is set on the counter. TimeLab seems to accurately detect this interval I started measuring various devices, and could never seem to get better than around 1x10^-6. Even my Rb was showing a 1 second ADEV of 10^-6. Finally I put the T-bolt on channel 1 with common mode on to both channels, and it still measures around 10^-6. A picture of that is attached. Surely this can't be right. I tried frequency mode and it gives ADEVs of 10^-12 on the Rb and T-bolt, as expected. I understand the issues with filtering that the 53131A does internally on this mode, but at least it shows my setup is working to some degree. It's TI mode that seems to be wonky. I'm probably doing something really stupid. Thanks for any help you all can suggest. Regards, Dan W adevtest.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Leap Second in press
Hello, This is an article published in one of the main newspapers in Spain, about the timekeeper at ROA, the institution responsible of legal time in Spain. http://www.elmundo.es/ciencia/2015/06/30/559189c622601d6b4e8b4594.html It is in spanish, but has pictures :) Regards, Javier ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] End Of The World
Any observations of anomalous behavior yet? From a BU-353: 57203 86380.750 $GPRMC,235940.000,A,3726.0893,N,12212.2627,W,0.52,64.49,300615 ,,*20 57203 86381.748 $GPRMC,235941.000,A,3726.0889,N,12212.2627,W,0.45,78.54,300615 ,,*2D 57203 86383.138 $GPRMC,235942.000,A,3726.0883,N,12212.2627,W,0.82,157.71,30061 5,,*14 57203 86383.752 $GPRMC,235943.000,A,3726.0874,N,12212.2628,W,1.71,186.96,30061 5,,*1A 57203 86384.750 $GPRMC,235944.000,A,3726.0866,N,12212.2630,W,1.33,180.14,30061 5,,*1D 57203 86385.752 $GPRMC,235944.000,A,3726.0858,N,12212.2631,W,1.10,178.01,30061 5,,*13 57203 86386.751 $GPRMC,235945.000,A,3726.0850,N,12212.2632,W,1.18,179.98,30061 5,,*10 57203 86388.136 $GPRMC,235946.000,A,3726.0842,N,12212.2630,W,1.67,146.83,30061 5,,*1C 57203 86388.752 $GPRMC,235947.000,A,3726.0836,N,12212.2627,W,1.15,129.24,30061 5,,*19 From a MR-350P 57203 86382.186 $GPRMC,235941.000,A,3726.0808,N,12212.2649,W,0.27,67.38,300615 ,,*2C 57203 86382.799 $GPRMC,235942.000,A,3726.0807,N,12212.2652,W,0.37,210.08,30061 5,,*1A 57203 86383.805 $GPRMC,235943.000,A,3726.0811,N,12212.2647,W,0.48,95.98,300615 ,,*26 57203 86384.807 $GPRMC,235944.000,A,3726.0812,N,12212.2647,W,0.17,210.63,30061 5,,*13 57203 86385.806 $GPRMC,235944.000,A,3726.0810,N,12212.2648,W,0.29,145.10,30061 5,,*14 57203 86387.188 $GPRMC,235945.000,A,3726.0809,N,12212.2647,W,0.39,174.68,30061 5,,*1E 57203 86387.807 $GPRMC,235946.000,A,3726.0806,N,12212.2647,W,0.54,173.43,30061 5,,*17 They both use SiRF chips. Above is just the GPRMC lines. Some of them are delayed enough to fall into the next second because every 5th second includes the GPGSV sentences. I'm pretty sure this was reported 3 years ago, I don't remember who found it, but I did remember to look back to find the insertion at midnight TAI rather than UTC. -- Overall, pretty boring. Jun 30 16:59:59 shuksan klogd: Clock: inserting leap second 23:59:60 UTC From a Z3801A: 57203 86397.032 T22015063023595830+1046 57203 86398.032 T22015063023595930+1047 57203 86399.034 T22015063023596030+103F 57203 86399.034 T2201507010030+1025 57204 0.034 T22015070101300102B 57204 1.032 T22015070102300102C 57204 2.032 T22015070103300102D From a Z3811A: 86397.050728 T22015063023595830+0045 86398.050667 T22015063023595930+0046 86399.050712 T22015063023596030+003E 86399.050765 T2201507010030+0024 0.050696 T2201507010132A 1.050750 T2201507010232B 2.050685 T2201507010332C Google's external time servers do their smear dance at 50 ms/hour starting 10 hours before the leap. It's linear rather than a fancy cosine. I'll get a graph together one of these days. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
Hi Andy, I think you would be guessing wrongly. The vast majority of watch owners don't want to ever have to set, wind, adjust the calendar, or in anyway think, or fiddle with their watch's time. They want it to just be right. In other words, their disinterest makes them the anti-time-nut. The engineering team that designed the watch is where the concerns about the watch always being right get turned into hardware. It costs them only a few days of an engineer's time to put, a temperature sensor, battery voltage sensor, and a table describing the nominal performance of the crystal at a normal range of temperatures and voltages, into the watch. It costs nothing on a per watch basis, as it is a trivial amount of additional silicon... silicon that resides within the necessary spaces between the pads used to connect the silicon die to the circuit board. As to per unit testing, the only testing required (after the initial design phase) is to program an offset into the watch that makes up for minor frequency variations in the crystal at nominal room temperature. Crystal manufacture is an imperfect process, so they have to do that anyway. -Chuck Harris Andy wrote: If this was normal back at the turn of the 20th century, why wouldn't Casio, and others at least do as well? Especially now that all electronic watches have a microprocessor built in... complete with temperature sensing diodes, battery monitors, and other nifty gadgets. I am guessing the vast majority of Casio owners don't especially care if their watch gains or loses a minute every month. So why bother to add sensors and circuitry to compensate for its environment? Furthermore, it requires setting the initial frequency on each watch built, to compensate for the crystal's initial error. And that jacks up the cost, perhaps more than adding those sensors would. Better to just churn them out with as little per-unit testing as possible. That's just my guess ... but who am I to say? Regards, Andy ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
Hi On Jun 29, 2015, at 6:03 PM, Andy ai.egrps...@gmail.com wrote: If this was normal back at the turn of the 20th century, why wouldn't Casio, and others at least do as well? Especially now that all electronic watches have a microprocessor built in... complete with temperature sensing diodes, battery monitors, and other nifty gadgets. I am guessing the vast majority of Casio owners don't especially care if their watch gains or loses a minute every month. Most don’t, but some do. The ones that do care talk a lot. When they go online with a “this watch is junk” post (with lots of data) it impacts the market. So why bother to add sensors and circuitry to compensate for its environment? Furthermore, it requires setting the initial frequency on each watch built, to compensate for the crystal's initial error. That’s been done since the original quartz watch designs. It’s done with a robot these days and is part of the checkout process on the module. It actually saves money. The precision of the crystal (and other parts) used can be lower if you do the calibration. Lower precision = better yield = lower cost. The chip in the watch likely goes into just about every watch they make. The size of the die is dictated by their ability to dice the wafer (roughly 1 mm square). Anything smaller than that makes no sense. However many devices you can pack into that much area, you get for free. With a modern process, that’s a *lot* of devices. One might think that running a much older process would be cheaper. That would only work if you made more watch chips (by wafer lots) than you make of everything else. That’s just not true. The answer is (as with everything else) that you keep up fairly close to a modern process. The process parameters for an ultra low power watch chip will be a bit different, but the geometry is dictated by the basic gear on the line. They all rumble down the same basic line at one of many (massively large) foundaries And that jacks up the cost, perhaps more than adding those sensors would. Better to just churn them out with as little per-unit testing as possible. An accurate watch “with all the testing” sells for $10. The market for an much less accurate watch would (presumably) be at an even lower sell point…. Bob That's just my guess ... but who am I to say? Regards, Andy ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Reeeely long term HP 5065A drift rate (13 year!)
Yes, same workbench and location! How about some of the 5065A owners helping out in a bigger sample? What I thought is that say on July the 4th a few owners measure their frequency offset to say at least 5X10-12th and then without changing the C-field for a year we could repeat the measurement next year and see what kind of results we get. Units would not have to stay powered on the entire time as long a you give them a day or so to warm up before the measurements. The Independence day 5065A offset club! Cheers, Corby ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Help with my ADEV measurement setup
Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup: - 53131A with the OCXO option. Calibrated against a T-bolt. I also did the TI Quik cal and it passed - I'm using RS-232 out with a null modem cable into a Serial-USB converter - Software is TimeLab in talk-only mode. 53131A check box is checked. - The counter is in TI mode, with a T-bolt on Channel 1 and DUT on Channel 2 - A delay of 1 second is set on the counter. TimeLab seems to accurately detect this interval I started measuring various devices, and could never seem to get better than around 1x10^-6. Even my Rb was showing a 1 second ADEV of 10^-6. Finally I put the T-bolt on channel 1 with common mode on to both channels, and it still measures around 10^-6. A picture of that is attached. Surely this can't be right. I tried frequency mode and it gives ADEVs of 10^-12 on the Rb and T-bolt, as expected. I understand the issues with filtering that the 53131A does internally on this mode, but at least it shows my setup is working to some degree. It's TI mode that seems to be wonky. I'm probably doing something really stupid. Thanks for any help you all can suggest. Regards, Dan W ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Reeeely long term HP 5065A drift rate (13 year!)
In message D17FBC384A414FEDB0C8C67AA73B00E5@pc52, Tom Van Baak writes: The key is that it was recently recalibrated at the same location it was originally calibrated. Make sense? The really interesting measurement would have the phase difference if the 5065A had been continously locked over those 13 years, but I suspect one does not ship a 5065A if it is continously locked :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Help with my ADEV measurement setup
Hi Are you using a PPS as the “start” and the 10 MHz as the “stop” or comparing two PPS signals? Bob On Jun 30, 2015, at 2:47 PM, Dan Watson watsondani...@gmail.com wrote: Hi, I'm trying to take some ADEV measurements with my 53131A, and I'm having some issues. This is my setup: - 53131A with the OCXO option. Calibrated against a T-bolt. I also did the TI Quik cal and it passed - I'm using RS-232 out with a null modem cable into a Serial-USB converter - Software is TimeLab in talk-only mode. 53131A check box is checked. - The counter is in TI mode, with a T-bolt on Channel 1 and DUT on Channel 2 - A delay of 1 second is set on the counter. TimeLab seems to accurately detect this interval I started measuring various devices, and could never seem to get better than around 1x10^-6. Even my Rb was showing a 1 second ADEV of 10^-6. Finally I put the T-bolt on channel 1 with common mode on to both channels, and it still measures around 10^-6. A picture of that is attached. Surely this can't be right. I tried frequency mode and it gives ADEVs of 10^-12 on the Rb and T-bolt, as expected. I understand the issues with filtering that the 53131A does internally on this mode, but at least it shows my setup is working to some degree. It's TI mode that seems to be wonky. I'm probably doing something really stupid. Thanks for any help you all can suggest. Regards, Dan W adevtest.png___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
Hi Even back in the 1970’s we used computing counters to read the 32 KHz. You get 7 digits in about 10 ms these days. It will take you longer to power up the module and stabilize it than the frequency reading takes. The semiconductor process for the watch chips has always been a bit odd. They never need anything faster than 32 KHz for a clock. They are after *very* low leakage. Back in the old days having it run at 1 V was considered strange. It’s pretty common today. They use the same tricks to dump an analog function into a digital process as the MCU people. It’s not a *great* analog sub system, but it’s good enough for the purpose. They may even calibrate the temperature and voltage when the set the frequency. That would let them get away with a *lot* of slop on those sub systems. If they digitize the temperature range from 0 to 50 C, that’s plenty for any normal environment the watch will see. A 5 bit ADC would be good enough for that task (with the proper full scale input). The same thing likely applies to the voltage. The circuit is unlikely to function below half voltage on the battery. Again a few bits of ADC will tell you everything you need to know to drive the table. I’d bet that they run a sigma delta and are quite happy with information at a “once a minute” sort of rate. There’s not a lot of “analog” stuff in that case. It would be pretty easy to dump onto the die. Bob On Jun 30, 2015, at 4:42 PM, Andy ai.egrps...@gmail.com wrote: Measuring a 32kHz frequency to ~100 PPB accuracy takes some time, even for ATE. Time is money. I didn't think the hardware to do the computations and the digital offset was any problem. I thought the temperature and voltage sensors might be, since they are analog. But you can integrate them into a good mixed technology IC process. I just didn't think that was what they are using. Andy ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Casio Watches 13 Year Drift in Seattle
Measuring a 32kHz frequency to ~100 PPB accuracy takes some time, even for ATE. Time is money. I didn't think the hardware to do the computations and the digital offset was any problem. I thought the temperature and voltage sensors might be, since they are analog. But you can integrate them into a good mixed technology IC process. I just didn't think that was what they are using. Andy ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
