Re: [time-nuts] Time nut newbie
li...@lazygranch.com said: A bit OT, but back in the day there was what amounted to an X-prize for a real accurate chronometer for navigation. Make that way back in the day. http://en.m.wikipedia.org/wiki/John_Harrison There is a good book out on that topic: Longitude by Dava Sobel There is also a fancy version with lots of very good pictures. I'll have to go find my copy so I can look at them again. -- 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 nut newbie
On Tue, Apr 30, 2013 at 7:40 PM, Jim Palfreyman jim77...@gmail.com wrote: Buy a cheap rubidium off ebay and use it to drive a micro-controller and write some clock software. That was exactly my solution but I'm waiting ti hear about his size, power and cost budget. If this has to run on Battery power for the entire year the Rb unit is not going to work The OP's 1 second per year goal is only asking for 3.2E-7 level performance if I did the math correctly. Even the $100 Rb is at least 100 times better than required. -- 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 nut newbie
On Tue, 30 Apr 2013 13:49:43 -0400 Tim Bastiann7...@yahoo.com wrote: I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. You want to read Vig's Quartz Crystal Tutorial. That explains a lot about where the instabilities of a crystal oscillator come from. You can find them (and a lot more) on http://www.ko4bb.com/ in the Manuals section. Have a look at different versions, as some interesting things were left out in the newer versions. An idea how to get to the stability you want without wasting too much power might be an MCXO. [1] gives a pretty decent overview of the way how they work including a schematic for an oscillator. [2] has some ideas how to simplify the circuit and get lower power. In your case, i guess it would be an idea to leave out the second stage frequency generation (the VCO or DDS) and generate a PPS directly from the microcontroller. Attila Kinali [1] A microcomputer compensated crystal oscillator using a dual-mode resonator, by Benjaminson and Stallings, 1989 [2] An Improved Method of MCXO, by Zhou, Liu, Wang, 2000 -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ 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 nut newbie
Hi It was tired old eyes and tiny numbers on the calculator ….That plus to much distraction to double check things. Bob On Apr 30, 2013, at 9:57 PM, Rex r...@sonic.net wrote: It doesn't affect the general magnitude conclusions by Bruce, but as long as we are making corrections, my calculator seems to think 60 * 60 * 24 * 12 = 1036800 seconds in 12 days, not 1024800. That does come out to 115.7 days for 1 sec error. Maybe the 12-day number was a typo? -Rex On 4/30/2013 12:57 PM, Bruce Griffiths wrote: 12 days is 1024800 s ie just over 1 million seconds so a frequency offset of 0.1ppm results in a time error of ~ 0.1s not 1s. 1sec error would occur in just under 116 days, Bruce Bob Camp wrote: Hi If you take a look down in the fine print on the OCXO spec, the aging rate is 100 ppb / year in the first year. If you are off by 0.1 ppm (100 ppb) your clock will gain a second in less than 12 days. 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. ___ 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 nut newbie
Hi, Tim: For what it is worth I've been down a similar road using various crystal controlled lab frequency standards to drive internet time servers. (I'm more of a plug and play person these days.) Some of these lab standards feature external DC power inputs and have a fairly low power drain.After running for a month my time server that uses an old (and probably very well aged) HP105B crystal standard as a reference is off by approx 1/100 of a second (it's hard to tell when looking at it via the internet.) At first I synchronized the time server with a 1pps signal from a GPS receiver, then I removed the 1pps signal and the let the time server free run using the HP105B as the time base. If you want to focus on building the clock vs building the reference some of the old crystal standards might be worth looking at and using a 1pps source from a GPS to initially sync your clock may be worth looking at as well. I'd be curious to hear what your longer term results are. You might also want to take a look at the http://tapr.org/kits_t2-mini.html for ways of converting the output of an OCXO to a 1pps pulse and syncing the pulses to an external source. Best regardsMark S Message: 7 Date: Wed, 1 May 2013 09:45:06 +0200 From: Attila Kinali att...@kinali.ch To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Time nut newbie Message-ID: 20130501094506.966146722efbbaf9c80e5...@kinali.ch Content-Type: text/plain; charset=UTF-8 On Tue, 30 Apr 2013 13:49:43 -0400 Tim Bastiann7...@yahoo.com wrote: I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year).? For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ? ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year.? Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. You want to read Vig's Quartz Crystal Tutorial. That explains a lot about where the instabilities of a crystal oscillator come from. You can find them (and a lot more) on http://www.ko4bb.com/ in the Manuals section. Have a look at different versions, as some interesting things were left out in the newer versions. An idea how to get to the stability you want without wasting too much power might be an MCXO. [1] gives a pretty decent overview of the way how they work including a schematic for an oscillator. [2] has some ideas how to simplify the circuit and get lower power. In your case, i guess it would be an idea to leave out the second stage frequency generation (the VCO or DDS) and generate a PPS directly from the microcontroller. Attila Kinali [1] A microcomputer compensated crystal oscillator using a dual-mode resonator, by Benjaminson and Stallings, 1989 [2] An Improved Method of MCXO, by Zhou, Liu, Wang, 2000 -- The people on 4chan are like brilliant psychologists who also happen to be insane and gross. -- unknown ___ 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] Time nut newbie
Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIX™ 4G on ATT ___ 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 nut newbie
Hi Tim -- Welcome! The easiest way to search the time-nuts list is to use Google and add the site:febo.com tag -- that will bring up hits in the list archive (as well as anything on my web site that might be pertinent). John On 4/30/2013 1:49 PM, Tim Bastian wrote: Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIX™ 4G on ATT ___ 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 nut newbie
n7...@yahoo.com said: My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). How do you get 10 seconds per year? The data sheet says 1 minute per year. -- 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 nut newbie
Hi If you take a look down in the fine print on the OCXO spec, the aging rate is 100 ppb / year in the first year. If you are off by 0.1 ppm (100 ppb) your clock will gain a second in less than 12 days. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Bastian Sent: Tuesday, April 30, 2013 1:50 PM To: time-nuts@febo.com Subject: [time-nuts] Time nut newbie Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIX 4G on ATT ___ 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 nut newbie
For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Do you have some power or size limitation? If not you can do a lot better than 1 second per year. But if it has to run for a year non-stop and fit in a pocket, well then it s a hard problem. I think if you could state the space, power and cost budget some one could suggest something. And then sample handheld GPS will always give you the best results. But that's cheating. -- 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 nut newbie
12 days is 1024800 s ie just over 1 million seconds so a frequency offset of 0.1ppm results in a time error of ~ 0.1s not 1s. 1sec error would occur in just under 116 days, Bruce Bob Camp wrote: Hi If you take a look down in the fine print on the OCXO spec, the aging rate is 100 ppb / year in the first year. If you are off by 0.1 ppm (100 ppb) your clock will gain a second in less than 12 days. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Bastian Sent: Tuesday, April 30, 2013 1:50 PM To: time-nuts@febo.com Subject: [time-nuts] Time nut newbie Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIX™ 4G on ATT ___ 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 nut newbie
Hi Either I need a new calculator or a new set of eyes Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Bruce Griffiths Sent: Tuesday, April 30, 2013 3:57 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Time nut newbie 12 days is 1024800 s ie just over 1 million seconds so a frequency offset of 0.1ppm results in a time error of ~ 0.1s not 1s. 1sec error would occur in just under 116 days, Bruce Bob Camp wrote: Hi If you take a look down in the fine print on the OCXO spec, the aging rate is 100 ppb / year in the first year. If you are off by 0.1 ppm (100 ppb) your clock will gain a second in less than 12 days. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Tim Bastian Sent: Tuesday, April 30, 2013 1:50 PM To: time-nuts@febo.com Subject: [time-nuts] Time nut newbie Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIXT 4G on ATT ___ 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] Time nut newbie
Hi Tim: You might look into the DS3232 which can be combined with a PIC to control the aging rate register. http://www.maximintegrated.com/datasheet/index.mvp/id/4984 Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html Tim Bastian wrote: Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIX™ 4G on ATT ___ 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 nut newbie
A bit OT, but back in the day there was what amounted to an X-prize for a real accurate chronometer for navigation. Make that way back in the day. http://en.m.wikipedia.org/wiki/John_Harrison Somehow I suspect everyone knows this story. ;-) -Original Message- From: Tim Bastiann7...@yahoo.com Sender: time-nuts-boun...@febo.com Date: Tue, 30 Apr 2013 13:49:43 To: time-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: [time-nuts] Time nut newbie Hi all, I'm a time nut newbie. My obsession started with the search for an accurate chronometer to carry on my boat for celestial navigation. Yes there still are a few of us left that practice the art. My current project is a quartz chronometer using a DS32Khz tcxo oscillator and two 74HC4060s (+ or- 10 seconds / year). For my next project I'm looking at an Abricon Part Number AOCJY2-10.000MHZ ocxo 5 ppb running through a pic and using the algorithm posted on http://www.romanblack.com/one_sec.htm. I'm shooting for + or - 1 seconds / year. Is there an archive of old posts that might be helpful in answering some of my questions and for getting ideas. Thanks, Tim KK4FQB Sent from my Motorola ATRIX™ 4G on ATT ___ 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 nut newbie
On 4/30/13 4:18 PM, li...@lazygranch.com wrote: A bit OT, but back in the day there was what amounted to an X-prize for a real accurate chronometer for navigation. Make that way back in the day. http://en.m.wikipedia.org/wiki/John_Harrison And he had a heck of a time collecting. I suspect collecting an X-prize might be easier (assuming you've met the conditions). The wikipedia article talks about the absolute error in the various clocks (5 seconds for transatlantic passage) but doesn't ever say how long that passage was. I did find another reference that gave 28.5 minutes of longitude over 5 months. If a degree of longitude is 4 minutes of time, then that's an error of about 120 seconds out of 13 million seconds, or 10ppm. That *is* impressive for a mechanical device. Another story (H5 clock in Kew gardens under supervision of George III) has 4.5 seconds error over 10 weeks, a bit less than 1 ppm. He had previously built temperature compensated pendulum clocks which achieved 1 second/month, which is about 0.3 ppm. The OP is shooting for about 30ppb (1 second/year). Of course, he'll spend a bit less time and money than Harrison did...grin ___ 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 nut newbie
It doesn't affect the general magnitude conclusions by Bruce, but as long as we are making corrections, my calculator seems to think 60 * 60 * 24 * 12 = 1036800 seconds in 12 days, not 1024800. That does come out to 115.7 days for 1 sec error. Maybe the 12-day number was a typo? -Rex On 4/30/2013 12:57 PM, Bruce Griffiths wrote: 12 days is 1024800 s ie just over 1 million seconds so a frequency offset of 0.1ppm results in a time error of ~ 0.1s not 1s. 1sec error would occur in just under 116 days, Bruce Bob Camp wrote: Hi If you take a look down in the fine print on the OCXO spec, the aging rate is 100 ppb / year in the first year. If you are off by 0.1 ppm (100 ppb) your clock will gain a second in less than 12 days. 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] Time nut newbie
Buy a cheap rubidium off ebay and use it to drive a micro-controller and write some clock software. On 1 May 2013 11:57, Rex r...@sonic.net wrote: It doesn't affect the general magnitude conclusions by Bruce, but as long as we are making corrections, my calculator seems to think 60 * 60 * 24 * 12 = 1036800 seconds in 12 days, not 1024800. That does come out to 115.7 days for 1 sec error. Maybe the 12-day number was a typo? -Rex On 4/30/2013 12:57 PM, Bruce Griffiths wrote: 12 days is 1024800 s ie just over 1 million seconds so a frequency offset of 0.1ppm results in a time error of ~ 0.1s not 1s. 1sec error would occur in just under 116 days, Bruce Bob Camp wrote: Hi If you take a look down in the fine print on the OCXO spec, the aging rate is 100 ppb / year in the first year. If you are off by 0.1 ppm (100 ppb) your clock will gain a second in less than 12 days. Bob __**_ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/** mailman/listinfo/time-nutshttps://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.
