Re: [time-nuts] Time in Phone System
bro...@pacific.net said: I expect that there's date and time information being sent in the header of every phone call, maybe even before the first ring along with the Caller ID info. Wiki says CallerID is sent between the first and second ring, and includes the date and time. http://en.wikipedia.org/wiki/Caller_ID#Operation -- 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] Time in Phone System
Works in France too. But someone has to call to get it set. Le 22 juil. 2014 à 06:40, Mark Sims a écrit : Yes, the caller ID data has time in it. There are chips out there that decode caller ID. I signaling format isially is the old Bell 202 modem protocol. The caller ID devices sort of half way answer the phone line when it detects the incoming call and the caller ID info is sent after the first ring. ___ 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] Time in Phone System
The data is formatted by the switch that connected the call. This could be a PBX that lives inside some small company or even in someone's house. Today these switches are computers and they would use the system time. So the time you are getting is just whatever time the caller's equipment thinks it is. But today I'd bet every phone switch is on the Internet and uses NTP to get the time. I had a PBX setup at home for a while. It is easy to do with open source software. Actually used an old modern card for signaling. I got rid of the system when it became to much trouble to maintain but now I get so many junk calls I'm thinking about setting it back up and having it automatically screen my calls. When I had it running I could load ANYTHING I wanted in the outgoing caller ID messages. The public phone system completely accepts whatever you put in there. Info here: trixbox http://www.voip-info.org/wiki/view/trixbox On Mon, Jul 21, 2014 at 9:40 PM, Mark Sims hol...@hotmail.com wrote: Yes, the caller ID data has time in it. There are chips out there that decode caller ID. I signaling format isially is the old Bell 202 modem protocol. The caller ID devices sort of half way answer the phone line when it detects the incoming call and the caller ID info is sent after the first ring. ___ 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] Time in Phone System
On Mon, Jul 21, 2014 at 11:01:19PM -0700, Hal Murray wrote: I expect that there's date and time information being sent in the header of every phone call, maybe even before the first ring along with the Caller ID info. Wiki says CallerID is sent between the first and second ring, and includes the date and time. http://en.wikipedia.org/wiki/Caller_ID#Operation Some old modems will happily decode it for you. I compared it to NTP at some point last year. The time stamp was only given to the nearest minute, and for my exchange it was pretty terrible - it was slow by about 90s for a few months. I was considering adding it to my leap second measurements, but there didn't seem to be much point. David. ___ 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] Time in Phone System
On 7/21/2014 9:07 PM, Brooke Clarke wrote: Hi: Every phone in my house that has an LCD shows the correct date time, but I have never set any of them. I expect that there's date and time information being sent in the header of every phone call, maybe even before the first ring along with the Caller ID info. Where to get technical details on the data format/protocol? My Panasonic cordless systems both have time settings in the base and use that. The Uniden cordless system is simpler and also uses the base system time setting. Settings for all three systems are thru a setup menu for the phone and have no provision for reading the times from any other source. FWIW, the Panasonic systems will override the text of the caller id if the number matches one you have entered in your directory. They are the type which have the voice reading of the caller id, doing a wonder job of mangling the pronunciations. Jim ___ 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] temperature sensor
For what it's worth: One possible source is through GE Thermometrics. They used to be Just Thermometrics bug GE bought them. The offer calibrated thermistors (At leas they used to offer calibration), with AB and C vales stated. Not sure what the costs are, but they make some pretty nice thermistors. http://www.ge-mcs.com/en/temperature.html Dan ___ 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] Time in Phone System
Need to specify the identification of the cordless phones. Panasonic KX-TGD22n (where n is the number of handsets) will set their time from the time included in the CID message. Anybody from a major telco know the accuracy of time on a DSL line? Bill Hawkins -Original Message- From: jim s Sent: Tuesday, July 22, 2014 7:56 AM My Panasonic cordless systems both have time settings in the base and use that. The Uniden cordless system is simpler and also uses the base system time setting. Settings for all three systems are thru a setup menu for the phone and have no provision for reading the times from any other source. ___ 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] temperature sensor
Chuck Harris cfhar...@erols.com wrote: Steam superheats only if the pressure is raised above standard pressure, otherwise, steam at standard pressure will be exactly 212F, or 100C. Saturated steam at standard pressure will be exactly 212F, or 100C. Superheated steam is steam raised above the saturation temperature, and so is dry, and could be any temperature above the boiling point at that pressure. Saturated steam under (positive or negative) pressure can boil at other temperatures, from memory (50 years ago!!) 30psi is 131 degC and 15psi is 115 degC. Steam in steam engines is generally dry, and is thus to some extent superheated. -- Brian Duffell YarmEngland ___ 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] temperature sensor
the broiling temperature is dependent of the atmospheric pressure! the water broils at 100C° only a see level! 73 Alex On 7/21/2014 11:56 AM, Alan Melia wrote: er not boiling watersteam. Water's boiling point is affected by the dissolved gasses and other contaminants. Alan G3NYK - Original Message - From: Bill Dailey docdai...@gmail.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, July 21, 2014 5:43 PM Subject: Re: [time-nuts] temperature sensor Ice water and boiling water coupled with altitude will give you two points. Sent from mobile On Jul 21, 2014, at 10:12 AM, Attila Kinali att...@kinali.ch wrote: On Mon, 21 Jul 2014 04:39:51 -0700 Alexander Pummer alex...@ieee.org wrote: NTC are not that very stable, they are amorphous material winch could recrystallize slowly and therefore change it's electrical behavior , PT100 style is more reliable since it is pure metal How long is the time constant for NTCs? I guess, it wouldn't matter for most of the measurements we do, as NTCs need to be calibrated before precision measurements anyways. Unless one measures over several months, or years. But on this timescales, i wouldn't really trust an off the shelf PT100 either. Not unless i measure its stability For use in GPSDOs and OCXOs, i guess it doesn't really matter, as long as the NTC stays within spec. There an external loop corrects for the variation/drift of the measurement. While we are at it: what is a good way to calibrate/characterize temperature sensors that is available to hobbyists? Attila Kinali -- I pity people who can't find laughter or at least some bit of amusement in the little doings of the day. I believe I could find something ridiculous even in the saddest moment, if necessary. It has nothing to do with being superficial. It's a matter of joy in life. -- Sophie Scholl ___ 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.
Re: [time-nuts] Noise and non-linear behaviour of ferrite transformers
Effectiveness of coax cable (at eliminating the effects of current through the shield) is often expressed as transfer impedance. Google it for more info, it has been extensively covered in the literature. Didier KO4BB On July 20, 2014 11:18:58 PM CDT, Chuck Harris cfhar...@erols.com wrote: Lots of meanings to the word induce. The one I was using was: to bring on, or about; effect; cause... I was not intending to imply transformer action. As an engineer I should know better than to try to use English to describe electrical phenomenon. My intention was to find out what: ...the skin depth of the coax shield gives up well before 60Hz... meant. Real life examples show that coax does just fine at shielding all the way down to DC... As long as you keep the currents flowing through the outside of the shield to a minimum. Which is done routinely by not connecting the ends of the shield so that current loops occur. Hardly a PA system exists that doesn't have a fairly long bit of unbalanced shielded cable at some high impedance high gain input. -Chuck Harris Alexander Pummer wrote: No, the current passing the outside f the shield will not induce any voltage inside of the coax, but the voltage drop caused by the current on the ohmic resistance [!!!] of the shield will show upbetween the two ends of the cable -- and that will show up as it was added to to the voltage which is carried on the center conductor of the coax. 73 Alex On 7/20/2014 6:10 PM, Chuck Harris wrote: I'm not sure what you are saying. skin depth = (2.6/sqrt(fhz))inches for copper. So, at 60Hz, skin depth = 0.336 inches. and at 100KHz, skin depth = 0.008 inches. and at 1MHz, skin depth = 0.0026 inches. Are you saying that at 60Hz, because the skin depth is deeper than the coax shield is thick, that current passing through the outside of the shield will induce voltage inside of the shield, and that at say, 100KHz where the skin depth is a little less than the shield thickness, or at 1 MHz, where the skin depth is only a small fraction of the thickness of the shield that it won't? Or something else? -Chuck Harris Bob Camp wrote: Hi The “coax is an antenna” problem comes in well before you get to DC. Even with no transformer involved, the skin depth of the coax shield gives up well above 60 Hz (and likely well above 100 KHz). If you want to do full isolation over a very wide range you need some combination of shielding and balanced lines. 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. -- Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do other things. ___ 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] Starting point for a WWVB project?
While looking for something else in the basement, I found this Ultralink 301/333 WWVB receiver: https://plus.google.com/u/0/photos/116677848251094111716/albums/6038922880078010001 I think I picked it up because the case looked useful, but I haven't molested it. It does not seem to work and I can find limited documentation on it. The remote pod labeled 301 seems to be the entire receiver. It contains the ferrite-loaded antenna and a Temic U4226 receiver chip. The other box seems to be supporting and interface circuitry. I make no claims for the unit other than it's cute. I have no use for it. If someone wants a pig in a poke, $36 will get it Priority Mailed to you (domestic US only). Thanks. 73, geo - n4ua ___ 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] temperature sensor
On Tue, 22 Jul 2014 01:17:03 +0100 Brian D gro...@planet3.freeuk.co.uk wrote: Saturated steam at standard pressure will be exactly 212F, or 100C. Stupid question: How to you ensure that the steam is saturated, while keeping a constant pressure? I think just buying some indium off ebay and use that as a melting/freezing reference is easier than the contraption needed to ensure fully saturated steam, with a low temperature gradient over the temperature sensor. That said. My investigations into stability of PT100 sensors reveal, that the quality ones can be less than 10mK/year, but hysteresis is in the same ball park (see [1]). Attila Kinali [1] Long term stability and hysteresis effects in Pt100 sensors used in industry, by Ljungblad, Holmstein, Josefson, Klevedal, 2013 -- I pity people who can't find laughter or at least some bit of amusement in the little doings of the day. I believe I could find something ridiculous even in the saddest moment, if necessary. It has nothing to do with being superficial. It's a matter of joy in life. -- Sophie Scholl ___ 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] Starting point for a WWVB project?
Geo if it uses that chip the thing should work even with the new format. You may want to place the antenna in a good position and give it a shot. You might like it. Regards Paul WB8TSL On Tue, Jul 22, 2014 at 1:10 PM, George Dubovsky n4ua...@gmail.com wrote: While looking for something else in the basement, I found this Ultralink 301/333 WWVB receiver: https://plus.google.com/u/0/photos/116677848251094111716/albums/6038922880078010001 I think I picked it up because the case looked useful, but I haven't molested it. It does not seem to work and I can find limited documentation on it. The remote pod labeled 301 seems to be the entire receiver. It contains the ferrite-loaded antenna and a Temic U4226 receiver chip. The other box seems to be supporting and interface circuitry. I make no claims for the unit other than it's cute. I have no use for it. If someone wants a pig in a poke, $36 will get it Priority Mailed to you (domestic US only). Thanks. 73, geo - n4ua ___ 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] new clock
Greetings, Started following the discussions recently and am learning a lot. Found the temperature sensor thread interesting. Measuring contact temperature (enclosure, heat sink) is a different problem than air temperature. For closing temperature control loops the absolute accuracy is often less important than things like speed of response (phase lag), both short and long term stability, and sensitivity (noise margin). Note that the NTC sensors, while having many positive attributes, are quite non-linear over an extended range. Calibration at the actual set point is necessary for absolute work. I am building the typical beginner clock project. A surplus Trimble VCO is used to clock a microprocessor. the micro has an internal 8x PLL which adds resolution in timing and simplifies the code. A GPS PPS is the reference and a DAC closes the loop. (Info if anyone interested). Instrumentation is limited. This all works ok and I am getting out old control texts to try to improve the performance but the voltage required by the VCO to maintain lock is dropping at an alarming rate - about 30 mV / week. Is this normal or do I have a lemon? What are good sources for non-lemon quartz oscillators? Thanks much in advance for any suggestions. Richard Warner ___ 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] temperature sensor
Group, I worked for Rosemount, a manufacturer of precision resistance thermometers, for many years. Platinum does have a well-known formula for temperature versus resistance, with second order corrections. But a sensor is not enough. You need to convert its physical property to a signal that is useful. This is done by some sort of temperature transmitter or conversion device. The device and the RTD are a system. The temperature system is calibrated as you would any other such system, by comparing it to a standard that is 10 times more accurate. So the question is, how accurate do you want it to be, just as it is for time and frequency standards. Boiling water with an ambient pressure correction is fine for some systems. More accuracy requires more purified water and a better pressure measurement. Similarly, the triple point of ice, water, and vapor depends on purity and knowledge of ambient conditions, as well as the heating effect of the stirrer. And that only gives you two points, with no knowledge of nonlinearity in between or outside them. There is plenty of literature on the subject, but it is not in the scope of precision time and frequency measurement. It is, however, summertime. Bill Hawkins ___ 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] new clock
An oscillator can take many weeks to settle in after being powered off / shipped / abused / looked at cross-eyed / etc. It typically takes a Thunderbolt a month or two to settle down after being shipped from China. ___ 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] temperature sensor
In a container, as steam condenses the pressure will drop. The steam will stay saturated. This is as long as the container contains steam only. Eventually, as the steam cools and condenses you will be left with a vacuum contains only minimal water vapor. Sent from mobile On Jul 22, 2014, at 2:11 PM, Attila Kinali att...@kinali.ch wrote: On Tue, 22 Jul 2014 01:17:03 +0100 Brian D gro...@planet3.freeuk.co.uk wrote: Saturated steam at standard pressure will be exactly 212F, or 100C. Stupid question: How to you ensure that the steam is saturated, while keeping a constant pressure? I think just buying some indium off ebay and use that as a melting/freezing reference is easier than the contraption needed to ensure fully saturated steam, with a low temperature gradient over the temperature sensor. That said. My investigations into stability of PT100 sensors reveal, that the quality ones can be less than 10mK/year, but hysteresis is in the same ball park (see [1]). Attila Kinali [1] Long term stability and hysteresis effects in Pt100 sensors used in industry, by Ljungblad, Holmstein, Josefson, Klevedal, 2013 -- I pity people who can't find laughter or at least some bit of amusement in the little doings of the day. I believe I could find something ridiculous even in the saddest moment, if necessary. It has nothing to do with being superficial. It's a matter of joy in life. -- Sophie Scholl ___ 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] new clock
Agree with Marks comments. Regards Paul On Tue, Jul 22, 2014 at 5:25 PM, Mark Sims hol...@hotmail.com wrote: An oscillator can take many weeks to settle in after being powered off / shipped / abused / looked at cross-eyed / etc. It typically takes a Thunderbolt a month or two to settle down after being shipped from China. ___ 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] new clock
Hi A lot depends on the oscillator. My fine old GR rack mount took most of 9 months to settle most of the way. It was still dropping in a year after that when I stopped watching it. Some of my T-Bolts took a week, some took a couple months…. Best thing you can do with any OCXO is just leave it on power. Bob On Jul 22, 2014, at 7:53 PM, paul swed paulsw...@gmail.com wrote: Agree with Marks comments. Regards Paul On Tue, Jul 22, 2014 at 5:25 PM, Mark Sims hol...@hotmail.com wrote: An oscillator can take many weeks to settle in after being powered off / shipped / abused / looked at cross-eyed / etc. It typically takes a Thunderbolt a month or two to settle down after being shipped from China. ___ 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.
Re: [time-nuts] Time in Phone System
On 7/21/2014 11:07 PM, Brooke Clarke wrote: Every phone in my house that has an LCD shows the correct date time, but I have never set any of them. I expect that there's date and time information being sent in the header of every phone call, maybe even before the first ring along with the Caller ID info CID is sent using FSK between the first and second rings, and includes the networks idea of TOD. Google can provide details. ___ 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.
