Re: [time-nuts] Dipleidoscope
On 2015-11-09 15:05, Larry McDavid wrote: Actually, it is an Edward John Dent dipleidoscope, or E. J. Dent, not I. E. Dent. But, hand engraving an "I" is much easier than engraving a "J" so many (not all) dipleidoscope covers were in fact engraved, "E. I. Dent." This letter substitution is similar to that seen in the often-engraved, "TRVTH" seen on buildings. Dent is a famous watch and chronometer maker, with offices in London. Edward John Dent designed, but did not live to see built, the famous London Great Clock, popularly known as, "Big Ben." Dent manufactured to Denison's design (later ennobled as Grimthorpe and that name used for the three-legged gravity escapement in that clock and others - see http://trin-hosts.trin.cam.ac.uk/clock for measurements of a similar clock) and Airy's specs (including first stroke of the hour to be within one second of GMT and performance telegraphed to Greenwich for checking) http://www.parliament.uk/about/living-heritage/building/palace/big-ben/building-clock-tower/building-great-clock [The bell and hammers were manufactured separately to Denison's design, and after only two months operation, the hammers cracked the bell, blamed on the hammers being more than double the maximum weight specified by the foundry https://en.wikipedia.org/wiki/Big_Ben#cite_ref-wbfbb_1-3 - a mistake unlikely to have been made by Dent.] Airy was the Astronomer Royal who established GMT, distributed it via telegraph wires throughout the UK, and compared time at the top and bottom of deep mine shafts to calculate gravitational differences and mean earth density: definitely a Time Nut. Surprisingly, the Dent & Company survives today and still produces custom clocks, spanning three centuries of clock making excellence. Alas, through personal correspondence, the Dent & Company today seems unaware of the Dent Dipleidoscope. They misspell it differently twice on their History page under Patents and 1843: diplied[ao]scope - http://www.dentlondon.com/about/history.php The company appears to have passed out of the family in the 1960s ending up with a different family owned jewellery and insignia private company http://www.aim25.ac.uk/cgi-bin/vcdf/detail?coll_id=16723&inst_id=118 -- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada ___ 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] Using borked Galileo sats to measure relativity
http://www.theregister.co.uk/2015/11/10/borked_eu_gps_satellites_braincheck_einstein/ Now, for 140E-6 bonus points, spot the error in the article... ___ 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] Low noise quartz crystal oscillator by Bruce Griffiths
Driscoll wrote a lot about oscillators over the years. I couldn't find anything specific to discontinuous operation. Do you have a titel of a paper related to this? What Driscoll was talking about was self limiting in a transistor. That is discontinuous operation, although Driscoll doesn't call it that. His earliest papers on this circuit go back to around 1972, and are in either UFFC proceedings and/or FCS. Many later papers cite these. The 2 transistor "Driscoll oscillator" fixes this problem by using an additional stage that limits instead of the oscillator transistor. Is the Burgoon patent you are refering to US4283691 "Crystal oscillator having low noise signal extraction circuit" ? Yes. ___ 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] NAVSTAR proteus GPS time and frequency unit
Magnus, Thanks for the detailed reply. I haven't had a need (read: no customer has paid me to do so...) to wallow through the GPS ICD, so that document is foreign to me. Your explanation clarifies the situation... Now it makes sense. Thanks! -Chuck Harris Magnus Danielson wrote: Chuck, Because all the leap-second info is kept in GPS-calender form, and essentially indicating current leap-second difference and which GPS week (modulo 256). Check out the ICD for yourself, IS-GPS-200H: 8<--- 20.3.3.5.2.4 Coordinated Universal Time (UTC). Page 18 of subframe 4 includes: (1) the parameters needed to relate GPS time to UTC, and (2) notice to the user regarding the scheduled future or recent past (relative to NAV message upload) value of the delta time due to leap seconds (ΔtLSF), together with the week number (WNLSF) and the day number (DN) at the end of which the leap second becomes effective. "Day one" is the first day relative to the end/start of week and the WNLSF value consists of eight bits which shall be a modulo 256 binary representation of the GPS week number (see paragraph 6.2.4) to which the DN is referenced. The user must account for the truncated nature of this parameter as well as truncation of WN, WNt, and WNLSF due to rollover of full week number (see paragraph 3.3.4(b)). The CS shall manage these parameters such that, when ΔtLS and ΔtLSF differ, the absolute value of the difference between the untruncated WN and WNLSF values shall not exceed 127. Depending upon the relationship of the effectivity date to the user's current GPS ... ___ 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] NAVSTAR proteus GPS time and frequency unit
Well for the heck of it I just fired the austron 2201 up. Date was circa 1980 or something way back. Guess the battery went. That said set the date and time to UTC and let it go. Almanac seems to grab a satellite every now and then but it does not go into the full track mode. I normally cheat this with a semi-automatic acquire and give it a list of know satellites. But will just let it run for a day or so. Regards Paul WB8TSL Need to watch it this is not my thread. On Mon, Nov 9, 2015 at 8:11 PM, Graham / KE9H wrote: > GPS Time ignores (does not deal with) "Leap Seconds." > It is dealt with in the software translation from GPS time to UTC or local > time. > That is part of the reason there is a 16 second time difference between GPS > Time and UTC/local time. > > --- Graham > > == > > On Mon, Nov 9, 2015 at 4:15 PM, Chuck Harris wrote: > > > Seems to me that there is more to this than just > > getting the displayed date wrong. > > > > It is true that the date will present wrongly, but > > what about leap seconds? > > > > If the GPS week rolls over at 1024, how will the > > GPS figure out which is the proper calendar date > > to apply the leap second? > > > > -Chuck Harris > > > > Hal Murray wrote: > > > >> > >> paulsw...@gmail.com said: > >> > >>> Hmmm then why do I have to figure it out at all? I don't care what the > >>> date > >>> says. > >>> > >> > >> Only that the Austron locks and does its frequency offset compare. It > >>> would > >>> be great not to have to do this. > >>> > >> > >> If you don't care about the date, then don't worry about it. > >> > >> It will do everything it did before. The only glitch is that the date > >> will > >> be off by 1024 weeks. > >> > >> > >> If you can't get the right date into your GPS unit, you can work around > >> the > >> issue in software. Just add 1024 weeks to the date until the date is > past > >> the build time of your fixup software. > >> > >> That assumes you have some software to work with. That won't help if > you > >> are > >> using a program that the vendor no longer supports. > >> > >> > >> ___ > > 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] NAVSTAR proteus GPS time and frequency unit
GPS Time ignores (does not deal with) "Leap Seconds." It is dealt with in the software translation from GPS time to UTC or local time. That is part of the reason there is a 16 second time difference between GPS Time and UTC/local time. --- Graham == On Mon, Nov 9, 2015 at 4:15 PM, Chuck Harris wrote: > Seems to me that there is more to this than just > getting the displayed date wrong. > > It is true that the date will present wrongly, but > what about leap seconds? > > If the GPS week rolls over at 1024, how will the > GPS figure out which is the proper calendar date > to apply the leap second? > > -Chuck Harris > > Hal Murray wrote: > >> >> paulsw...@gmail.com said: >> >>> Hmmm then why do I have to figure it out at all? I don't care what the >>> date >>> says. >>> >> >> Only that the Austron locks and does its frequency offset compare. It >>> would >>> be great not to have to do this. >>> >> >> If you don't care about the date, then don't worry about it. >> >> It will do everything it did before. The only glitch is that the date >> will >> be off by 1024 weeks. >> >> >> If you can't get the right date into your GPS unit, you can work around >> the >> issue in software. Just add 1024 weeks to the date until the date is past >> the build time of your fixup software. >> >> That assumes you have some software to work with. That won't help if you >> are >> using a program that the vendor no longer supports. >> >> >> ___ > 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] NAVSTAR proteus GPS time and frequency unit
Chuck, Because all the leap-second info is kept in GPS-calender form, and essentially indicating current leap-second difference and which GPS week (modulo 256). Check out the ICD for yourself, IS-GPS-200H: 8<--- 20.3.3.5.2.4 Coordinated Universal Time (UTC). Page 18 of subframe 4 includes: (1) the parameters needed to relate GPS time to UTC, and (2) notice to the user regarding the scheduled future or recent past (relative to NAV message upload) value of the delta time due to leap seconds (ΔtLSF), together with the week number (WNLSF) and the day number (DN) at the end of which the leap second becomes effective. "Day one" is the first day relative to the end/start of week and the WNLSF value consists of eight bits which shall be a modulo 256 binary representation of the GPS week number (see paragraph 6.2.4) to which the DN is referenced. The user must account for the truncated nature of this parameter as well as truncation of WN, WNt, and WNLSF due to rollover of full week number (see paragraph 3.3.4(b)). The CS shall manage these parameters such that, when ΔtLS and ΔtLSF differ, the absolute value of the difference between the untruncated WN and WNLSF values shall not exceed 127. Depending upon the relationship of the effectivity date to the user's current GPS time, the following three different UTC/GPS-time relationships exist: a. Whenever the effectivity time indicated by the WNLSF and the DN values is not in the past (relative to the user's present time), and the user's present time does not fall in the time span which starts at six hours prior to the effectivity time and ends at six hours after the effectivity time, the UTC/GPS-time relationship is given by tUTC = (tE - ΔtUTC) [modulo 86400 seconds] where tUTC is in seconds and ΔtUTC = ΔtLS + A0 + A1 (tE - tot + 604800 (WN - WNt)), seconds; tE =GPS time as estimated by the user after correcting tSV for factors described in paragraph 20.3.3.3.3 as well as for selective availability (SA) (dither) effects; ΔtLS = delta time due to leap seconds; A0 and A1 = constant and first order terms of polynomial; tot = reference time for UTC data (reference 20.3.4.5); WN = current week number (derived from subframe 1); WNt = UTC reference week number. The estimated GPS time (tE) shall be in seconds relative to end/start of week. During the normal and short-term extended operations, the reference time for UTC data, tot, is some multiple of 212 seconds occurring approximately 70 hours after the first valid transmission time for this UTC data set (reference 20.3.4.5). The reference time for UTC data (tot) shall be referenced to the start of that week whose number (WNt) is given in word eight of page 18 in subframe 4. The WNt value consists of eight bits which shall be a modulo 256 binary representation of the GPS week number (see paragraph 6.2.4) to which the tot is referenced. The user must account for the truncated nature of this parameter as well as truncation of WN, WNt, and WNLSF due to rollover of full week number (see paragraph 3.3.4(b)). The CS shall manage these parameters such that the absolute value of the difference between the untruncated WN and WNt values shall not exceed 127. b. Whenever the user's current time falls within the time span of six hours prior to the effectivity time to six hours after the effectivity time, proper accommodation of the leap second event with a possible week number transition is provided by the following expression for UTC: tUTC = W[modulo (86400 + ΔtLSF - ΔtLS)], seconds; where W = (tE - ΔtUTC - 43200) [modulo 86400] + 43200, seconds; and the definition of ΔtUTC (as given in 20.3.3.5.2.4a above) applies throughout the transition period. Note that when a leap second is added, unconventional time values of the form 23:59:60.xxx are encountered. Some user equipment may be designed to approximate UTC by decrementing the running count of time within several seconds after the event, thereby promptly returning to a proper time indication. Whenever a leap second event is encountered, the user equipment must consistently implement carries or borrows into any year/week/day counts. c. Whenever the effectivity time of the leap second event, as indicated by the WNLSF and DN values, is in the "past" (relative to the user's current time), and the user’s current time does not fall in the time span as given above in 20.3.3.5.2.4b, the relationship previously given for tUTC in 20.3.3.5.2.4a above is valid except that the value of ΔtLSF is substituted for ΔtLS. The CS will coordinate the update of UTC parameters at a future upload so as to maintain a proper continuity of the tUTC time scale. --->8 The GPS date gears is different to normal dates, and all relevant events is related in the form of these gears (or own set of scales if you so like). The UTC information is no exception, it is more of the same, so getting these things right follows the same pattern. You can do all
Re: [time-nuts] HP 53131A display dim
Hi With only one or two digits - check the connections and make sure it’s not a driver issue. (Yes, it’s a custom part so either you get a parts unit counter or a HP spare part). Bob > On Nov 9, 2015, at 1:12 PM, cdel...@juno.com wrote: > > Hi, > > Thanks for the replies. > > Only a couple digits are dim so I guess it must be the VFD? > > I suppose the only source is to find an otherwise dead unit to strip it > out of? > > 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] NAVSTAR proteus GPS time and frequency unit
Seems to me that there is more to this than just getting the displayed date wrong. It is true that the date will present wrongly, but what about leap seconds? If the GPS week rolls over at 1024, how will the GPS figure out which is the proper calendar date to apply the leap second? -Chuck Harris Hal Murray wrote: paulsw...@gmail.com said: Hmmm then why do I have to figure it out at all? I don't care what the date says. Only that the Austron locks and does its frequency offset compare. It would be great not to have to do this. If you don't care about the date, then don't worry about it. It will do everything it did before. The only glitch is that the date will be off by 1024 weeks. If you can't get the right date into your GPS unit, you can work around the issue in software. Just add 1024 weeks to the date until the date is past the build time of your fixup software. That assumes you have some software to work with. That won't help if you are using a program that the vendor no longer supports. ___ 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] Dipleidoscope
Actually, it is an Edward John Dent dipleidoscope, or E. J. Dent, not I. E. Dent. But, hand engraving an "I" is much easier than engraving a "J" so many (not all) dipleidoscope covers were in fact engraved, "E. I. Dent." This letter substitution is similar to that seen in the often-engraved, "TRVTH" seen on buildings. Dent is a famous watch and chronometer maker, with offices in London. Edward John Dent designed, but did not live to see built, the famous London Great Clock, popularly known as, "Big Ben." Surprisingly, the Dent & Company survives today and still produces custom clocks, spanning three centuries of clock making excellence. Alas, through personal correspondence, the Dent & Company today seems unaware of the Dent Dipleidoscope. Larry On 11/9/2015 9:16 AM, James Hazi wrote: Hi, I am trying to get in touch with larry McDavid , I came across a I.E. Dent Dipleidoscope and I was wondering if he would give me some insight on it. I would be able to send some pictures if you would request. Thanks, Jim -- Best wishes, Larry McDavid W6FUB Anaheim, California (SE of Los Angeles, near Disneyland) ___ 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] Dipleidoscope
I have several original printed Dent manuals as part of my dipleidoscope collection. I have confirmed identifying instant of local solar noon within 6 seconds; with the optional magnifying telescope, three seconds is possible. Not bad for the common man in 1850! Sent via the Samsung GALAXY S5 Original message From: Brent Date: 11/09/2015 9:39 AM (GMT-08:00) To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Dipleidoscope Cool! - never new such a thing existed. I presume you've googled and come up with the book by Dent on its use via google books? https://books.google.com/books?id=9QlbQAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false Brent On Mon, Nov 9, 2015 at 12:16 PM, James Hazi wrote: > Hi, I am trying to get in touch with larry McDavid , I came across a I.E. > Dent Dipleidoscope and I was wondering if he would give me some insight on > it. I would be able to send some pictures if you would request. Thanks, 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. > ___ 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] NAVSTAR proteus GPS time and frequency unit
OK great conversation. Not sure when but far sooner then later will fire the system up and just let it run for a week. Regards Paul WB8TSL On Mon, Nov 9, 2015 at 1:09 PM, Hal Murray wrote: > > paulsw...@gmail.com said: > > Hmmm then why do I have to figure it out at all? I don't care what the > date > > says. > > > Only that the Austron locks and does its frequency offset compare. It > would > > be great not to have to do this. > > If you don't care about the date, then don't worry about it. > > It will do everything it did before. The only glitch is that the date will > be off by 1024 weeks. > > > If you can't get the right date into your GPS unit, you can work around the > issue in software. Just add 1024 weeks to the date until the date is past > the build time of your fixup software. > > That assumes you have some software to work with. That won't help if you > are > using a program that the vendor no longer supports. > > > -- > 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. > ___ 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] Dipleidoscope
Cool! - never new such a thing existed. I presume you've googled and come up with the book by Dent on its use via google books? https://books.google.com/books?id=9QlbQAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false Brent On Mon, Nov 9, 2015 at 12:16 PM, James Hazi wrote: > Hi, I am trying to get in touch with larry McDavid , I came across a I.E. > Dent Dipleidoscope and I was wondering if he would give me some insight on > it. I would be able to send some pictures if you would request. Thanks, 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. > ___ 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] HP 53131A display dim
Hi, Thanks for the replies. Only a couple digits are dim so I guess it must be the VFD? I suppose the only source is to find an otherwise dead unit to strip it out of? 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.
Re: [time-nuts] Dipleidoscope
James, I have several Dent Dipleidoscopes and gave a presentation on them at a recent NASS Conference. Please feel free to contact me. Lacking an observatory transit instrument, they were the best source of accurate time in the 1850's. Larry lmcda...@lmceng.com On 11/9/2015 9:16 AM, James Hazi wrote: Hi, I am trying to get in touch with larry McDavid , I came across a I.E. Dent Dipleidoscope and I was wondering if he would give me some insight on it. I would be able to send some pictures if you would request. Thanks, Jim -- Best wishes, Larry McDavid W6FUB Anaheim, California (SE of Los Angeles, near Disneyland) ___ 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] NAVSTAR proteus GPS time and frequency unit
paulsw...@gmail.com said: > Hmmm then why do I have to figure it out at all? I don't care what the date > says. > Only that the Austron locks and does its frequency offset compare. It would > be great not to have to do this. If you don't care about the date, then don't worry about it. It will do everything it did before. The only glitch is that the date will be off by 1024 weeks. If you can't get the right date into your GPS unit, you can work around the issue in software. Just add 1024 weeks to the date until the date is past the build time of your fixup software. That assumes you have some software to work with. That won't help if you are using a program that the vendor no longer supports. -- 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] Dipleidoscope
Hi Jim: There's some info at: http://www.prc68.com/I/Dent.shtml Mail_Attachment -- Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html http://www.prc68.com/I/DietNutrition.html James Hazi wrote: Hi, I am trying to get in touch with larry McDavid , I came across a I.E. Dent Dipleidoscope and I was wondering if he would give me some insight on it. I would be able to send some pictures if you would request. Thanks, 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. ___ 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] Dipleidoscope
Hi, I am trying to get in touch with larry McDavid , I came across a I.E. Dent Dipleidoscope and I was wondering if he would give me some insight on it. I would be able to send some pictures if you would request. Thanks, 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] NAVSTAR proteus GPS time and frequency unit
Hmmm then why do I have to figure it out at all? I don't care what the date says. Only that the Austron locks and does its frequency offset compare. It would be great not to have to do this. Regards Paul WB8TSL On Sun, Nov 8, 2015 at 9:06 PM, Magnus Danielson wrote: > Paul, > > On 11/09/2015 01:07 AM, paul swed wrote: > >> Because the roll over is a pain. >> Thats good engineering if they checked that far. >> What happens if you have a receiver that doesn't handle it correctly is >> you >> do not tend to get satellite lock because the dates all wrong. >> > > No. The GPS internal date-format avoids this issue altogether, it's the > conversion from the GPS date gears to "user dates" that gets confused due > to lack of additional bits for GPS weeks, but the GPS receiver can keep > operate even if the GPS weeks wrap, with very little software concern. So, > after the GPS week wrapping, wherever it occurs for a receiver, only means > that the published user date becomes wrong, not the GPS system internal > date, the receiver keeps working through it, whatever it is. > > You cheat this "The pain part" by figuring out what the date should have >> been by subtracting 1024 weeks. Seems easy right. Nope. >> > > I've only seen receivers fail in their date conversion, and in exactly > 1024 weeks. > > Cheers, > Magnus > > > That works for the old austron. But as I say serious thinking. There are >> some online tools that help. But it all gets old very fast. >> Regards >> Paul >> WB8TSL >> >> On Sun, Nov 8, 2015 at 4:01 PM, Rob Sherwood. wrote: >> >> Why is this an issue? >>> >>> Sent from my iPad >>> >>> On Nov 8, 2015, at 1:00 PM, "Brendan Giles" >>> wrote: >>> I was the project manager who was in charge of the NAVSTAR proteus GPS >>> time and frequency unit.The two GPS rollover dates 1999/2018 were tested >>> in >>> product test plan. Also various dates were checked upto 2037 for the PC >>> output message. >>> Brendan Giles ___ 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. -- If this email is spam, report it to >>> https://support.onlymyemail.com/view/report_spam/ODExMjI6MTgyMzU3ODA4MDpyb2JAbmMwYi5jb206ZGVsaXZlcmVk >>> ___ >>> 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] HP 3335A for the impoverished experimenter
The phase noise of the 3335A is typically much better than spec. Definitely way better than a 3336C and has one of the worlds best laser-trimmed attenuators. The 8642A and 8662A are better on phase noise, but much harder to keep working. Anyone wanting a great signal generator should jump at this. Rob NC0B Sent from my iPad > On Nov 9, 2015, at 5:31 AM, "Bill Hawkins" wrote: > > > > Group, > > I have the subject frequency synthesizer and the expanded foam shipping > container it arrived in. > > I also have to move to an apartment in a life care community in two > weeks. > > True, the focus of this list seems to be on 10 MHz, but if you'd like to > experiment with precision frequencies between 200 Hz and 80 MHz, this is > for you. > > The instrument has been checked with a few minor repairs. It is fully > functional as measured with a Racal 1992 counter and rubidium external > standard. Amplitude was checked with a Triplett 630 VOM, so accuracy of > the measurement was 5% and didn't go down to millivolts. A scope could > see that there was output that low and seemed to follow the dB ratios. > > I'm asking $200 for it shipped in continental US. The Racal counter is > available for $100 shipped. > > At this point I don't care if it goes to a dealer who sells it for > $1500. But if there are multiple requests, it goes to the best > impoverished experimenter story. > > Please reply directly to b...@iaxs.net, not the list. > > It's been fun. > > Bill Hawkins > > P.S. Also have a 3335A parts unit and an Efratom FRK L rubidium pulled > from a Collins Omega navigation set, oh, and a set of the older Lucent > RFTG XO and RB units. The newer units don't have RB oscillators. > > ___ > 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. > > > > -- > If this email is spam, report it to > https://support.onlymyemail.com/view/report_spam/ODExMjI6MTgyMzY3NTg4MTpyb2JAbmMwYi5jb206ZGVsaXZlcmVk > ___ 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] HP 53131A display dim
This may sound silly but aside from the failing capacitors that cause displays to dim, the emissions falling and other esoteric issues, in my years repairing VCRs with VFDs I most often found a good clean of the glass and bezel would improve the brightness a considerable amount. On 9 Nov 2015 05:30, "Chuck Harris" wrote: > The biggest cause of failure with VFD's that I have seen > is the filament voltage drops too low. Usually it is a bad > capacitor in the supply, or a drifting resistor on the regulator. > > I have a VFD on an alarm clock made by GE back in 1980 that > has been running 24/7 since it was bought, and is still way too > bright. I make my wife prop something to block it so that it > doesn't keep me awake. > > -Chuck Harris > > cdel...@juno.com wrote: > >> Anyone know about these displays? >> >> If the display is getting dim do I need a new VFD module? >> >> Thanks, >> >> 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. > ___ 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] HP 3335A for the impoverished experimenter
Group, I have the subject frequency synthesizer and the expanded foam shipping container it arrived in. I also have to move to an apartment in a life care community in two weeks. True, the focus of this list seems to be on 10 MHz, but if you'd like to experiment with precision frequencies between 200 Hz and 80 MHz, this is for you. The instrument has been checked with a few minor repairs. It is fully functional as measured with a Racal 1992 counter and rubidium external standard. Amplitude was checked with a Triplett 630 VOM, so accuracy of the measurement was 5% and didn't go down to millivolts. A scope could see that there was output that low and seemed to follow the dB ratios. I'm asking $200 for it shipped in continental US. The Racal counter is available for $100 shipped. At this point I don't care if it goes to a dealer who sells it for $1500. But if there are multiple requests, it goes to the best impoverished experimenter story. Please reply directly to b...@iaxs.net, not the list. It's been fun. Bill Hawkins P.S. Also have a 3335A parts unit and an Efratom FRK L rubidium pulled from a Collins Omega navigation set, oh, and a set of the older Lucent RFTG XO and RB units. The newer units don't have RB oscillators. ___ 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] Low noise quartz crystal oscillator by Bruce Griffiths
Hoi Will, On Mon, 09 Nov 2015 14:09:27 +1300 Will wrote: > Ham Radio Magazine used to be available on archive.org but has been > removed. 73 Magazine is still available. > > CD's of it are available (expensive). > > I'll look later and see which issue it was. Thanks. I already got a copy of both articles. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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.
