Hi Ron: I think HP pioneered that method in one of their hand held calculators (PH35 or PH41)? -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html -------- Original Message -------- >> In your case, the car sits in an environment that matches their test >> setup well. In my case �\200� not so much. > FWIW, mine drifts pretty badly. It's in an aftermarket stereo, and I > don't remember when I bought it (I moved it from my previous car). > > I assume that all quartz clocks and watches these days use "inhibition > conpensation". > > https://en.wikipedia.org/wiki/Quartz_clock#Inhibition_compensation > > > > > _______________________________________________ > 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. >

Nice article in Wikipedia. Didn't see any familiar names in the reference list, though. Seems to me inhibition compensation is useful for compensating for the variation in purchased crystal frequencies, but not for temperature compensation. Also seems to me that a watch spends 2/3 of a day at wrist temperature and 1/3 at bedroom temperature, which varies with the seasons. Would a ceramic capacitor crafted for a certain temperature coefficient work? Can the fork have a crafted tempco? Bill Hawkins -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Ron Bean Sent: Sunday, April 09, 2017 12:05 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Car Clock drift - the lowly 32kHz tuning fork crystal specs >In your case, the car sits in an environment that matches their test >setup well. In my case ?\200? not so much. FWIW, mine drifts pretty badly. It's in an aftermarket stereo, and I don't remember when I bought it (I moved it from my previous car). I assume that all quartz clocks and watches these days use "inhibition conpensation". https://en.wikipedia.org/wiki/Quartz_clock#Inhibition_compensation

Hi The compensation process either for a clock or a watch has been embedded in the IC for a lot of years now. They do a pulse add / pulse drop approach to “level out” the 1 pps drive to the display. Temperature does not move fast enough that averaging things over a minute is an issue. That gives them < 1 ppm resolution which is better than what they know about temperature. It is also good enough to set it on “at the factory” to run at whatever rate they decide on. In most cases the nominal target is for the watch or car clock to run a bit fast (= it’s never slow) rather than try to set it dead on. Most people yell at watches when they are late …. Bob > On Apr 9, 2017, at 4:11 PM, Bill Hawkins <bill.iaxs@pobox.com> wrote: > > Nice article in Wikipedia. Didn't see any familiar names in the > reference list, though. > > Seems to me inhibition compensation is useful for compensating for the > variation in purchased crystal frequencies, but not for temperature > compensation. > > Also seems to me that a watch spends 2/3 of a day at wrist temperature > and 1/3 at bedroom temperature, which varies with the seasons. > > Would a ceramic capacitor crafted for a certain temperature coefficient > work? Can the fork have a crafted tempco? > > Bill Hawkins > > > -----Original Message----- > From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Ron > Bean > Sent: Sunday, April 09, 2017 12:05 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Car Clock drift - the lowly 32kHz tuning fork > crystal specs > >> In your case, the car sits in an environment that matches their test >> setup well. In my case ?\200? not so much. > > FWIW, mine drifts pretty badly. It's in an aftermarket stereo, and I > don't remember when I bought it (I moved it from my previous car). > > I assume that all quartz clocks and watches these days use "inhibition > conpensation". > > https://en.wikipedia.org/wiki/Quartz_clock#Inhibition_compensation > > > _______________________________________________ > 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.

actually it does not compensate for temperature it is just for reduce the production cost for the crystal. We --Jean Hoerni [founder of intersil, Eurosil and one of the traitors who started Fairchild Semiconductor] and me -- made something very similar at the time of begin of the quartz clock era for Lipp a French watch maker in Bezancon [a city an France the spelling is most likely not correct]. The company exhibited it at the Basler exhibition of Horology, the clock was simple good working and not to expensive, Ebachos --OMEGA -- people visited the booth, they also had their quartz clock which was much more expensive -- they looked, the Lipp clock and told na there are Rolls-Royce s and deux chevaux [that was a simple little ugly but very reliably French car ] as response Mr. Hoerni told them yes, and there are technologies not known in your house, the Omega people recognized him and walked away quietly... 73 Alex On 4/9/2017 1:11 PM, Bill Hawkins wrote: > Nice article in Wikipedia. Didn't see any familiar names in the > reference list, though. > > Seems to me inhibition compensation is useful for compensating for the > variation in purchased crystal frequencies, but not for temperature > compensation. > > Also seems to me that a watch spends 2/3 of a day at wrist temperature > and 1/3 at bedroom temperature, which varies with the seasons. > > Would a ceramic capacitor crafted for a certain temperature coefficient > work? Can the fork have a crafted tempco? > > Bill Hawkins > > > -----Original Message----- > From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Ron > Bean > Sent: Sunday, April 09, 2017 12:05 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Car Clock drift - the lowly 32kHz tuning fork > crystal specs > >> In your case, the car sits in an environment that matches their test >> setup well. In my case ?\200? not so much. > FWIW, mine drifts pretty badly. It's in an aftermarket stereo, and I > don't remember when I bought it (I moved it from my previous car). > > I assume that all quartz clocks and watches these days use "inhibition > conpensation". > > https://en.wikipedia.org/wiki/Quartz_clock#Inhibition_compensation > > > _______________________________________________ > 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. > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2016.0.8012 / Virus Database: 4769/14275 - Release Date: 04/09/17

Hi > On Apr 9, 2017, at 10:01 PM, Alex Pummer <alex@pcscons.com> wrote: > > actually it does not compensate for temperature it is just for reduce the production cost for the crystal. We --Jean Hoerni [founder of intersil, Eurosil and one of the traitors who started Fairchild Semiconductor] and me -- made something very similar at the time of begin of the quartz clock era for Lipp a French watch maker in Bezancon [a city an France the spelling is most likely not correct]. The company exhibited it at the Basler exhibition of Horology, the clock was simple good working and not to expensive, Ebachos --OMEGA -- people visited the booth, they also had their quartz clock which was much more expensive -- they looked, the Lipp clock and told na there are Rolls-Royce s and deux chevaux [that was a simple little ugly but very reliably French car ] as response Mr. Hoerni told them yes, and there are technologies not known in your house, the Omega people recognized him and walked away quietly... > > 73 > > Alex Just to put this in context. The “prior state of the art” was to have a trimmer capacitor in the watch (or clock) module to set it on frequency. That’s why it was obvious from a quick look that something was different. There were semiconductor companies making watch modules at the same time still using trimmer capacitors. The pulse drop / add was not at all an “obvious” solution at the time. Bob > > > On 4/9/2017 1:11 PM, Bill Hawkins wrote: >> Nice article in Wikipedia. Didn't see any familiar names in the >> reference list, though. >> >> Seems to me inhibition compensation is useful for compensating for the >> variation in purchased crystal frequencies, but not for temperature >> compensation. >> >> Also seems to me that a watch spends 2/3 of a day at wrist temperature >> and 1/3 at bedroom temperature, which varies with the seasons. >> >> Would a ceramic capacitor crafted for a certain temperature coefficient >> work? Can the fork have a crafted tempco? >> >> Bill Hawkins >> >> >> -----Original Message----- >> From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Ron >> Bean >> Sent: Sunday, April 09, 2017 12:05 PM >> To: Discussion of precise time and frequency measurement >> Subject: Re: [time-nuts] Car Clock drift - the lowly 32kHz tuning fork >> crystal specs >> >>> In your case, the car sits in an environment that matches their test >>> setup well. In my case ?\200? not so much. >> FWIW, mine drifts pretty badly. It's in an aftermarket stereo, and I >> don't remember when I bought it (I moved it from my previous car). >> >> I assume that all quartz clocks and watches these days use "inhibition >> conpensation". >> >> https://en.wikipedia.org/wiki/Quartz_clock#Inhibition_compensation >> >> >> _______________________________________________ >> 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. >> >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2016.0.8012 / Virus Database: 4769/14275 - Release Date: 04/09/17 > > _______________________________________________ > 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.