Re: [time-nuts] Looking For Brandywine GPS-4 User Manual

2006-12-20 Thread Robert E. Martinson
Hi, Tried sending it via this list, but there is a 128KB limit. Please send me your direct email address. 73, Bob N1VQR -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jason Rabel Sent: Wednesday, December 20, 2006 8:45 PM To: 'Discussion of precise ti

Re: [time-nuts] A Bunch Of Lucent RFTG-m-RB units on eBay This Morning!

2006-12-20 Thread David I. Emery
On Wed, Dec 20, 2006 at 10:58:02AM -0600, Jason Rabel wrote: > Just a heads up, if you search eBay for 'Lucent RFTG' you will see someone > has listed a bunch of the rubidium units today with BIN of $130. These are > not the previously listed RFG's. The RFTG have the built-in GPS receiver (I > thin

Re: [time-nuts] Looking for QST Jan 1990 Article on Crystal S, Q & R testing By DeMaw

2006-12-20 Thread Didier Juges
I did just that to check the 50 MHz crystal in my HP 3586 and convince myself it was not dead. The 50 MHz VCXO did not oscillate, for some reason, and finding a replacement crystal would have been a long shot and would have probably cost more than I paid for the instrument. Seeing the proper re

[time-nuts] Looking For Brandywine GPS-4 User Manual

2006-12-20 Thread Jason Rabel
Does anyone by chance have a PDF manual for a Brandywine GPS-4 (not the PDF spec sheet on their site)? Also, if it's not mentioned in the manual, what is the power input for the unit? I've tried contacting the Brandywine people a couple times, have not received a reply. :( Thanks, Jason ___

Re: [time-nuts] Looking for QST Jan 1990 Article on Crystal S, Q & R testing By DeMaw

2006-12-20 Thread Brooke Clarke
Hi Mike: I've received an email asking about where to purchase a crystal activity meter and although I have a hand held unit, see: http://www.pacificsites.com/~brooke/Xam.html don't want to part with it. This is an older unit that uses PNP transistors. I'm now thinking about how to build one u

[time-nuts] 9825a printer

2006-12-20 Thread tom
got a working hp 9825a that has a strip printer that works also. the printer prints in double size instead of regular size and i have not found the command to reduce the double size printing. would any one on this reflector know what that command would be? tom [EMAIL PROTECTED] ___

Re: [time-nuts] Looking for QST Jan 1990 Article on Crystal S, Q & R testing By DeMaw

2006-12-20 Thread Mike Feher
Brooke - In that case why do not just use a signal generator like an 8640B with the crystal in series with the hot lead and then the other side of the crystal terminated in 1K or so. Then you can put a scope across the 1K resistor and watch the scope as you tune across the suspected resonant frequ

Re: [time-nuts] A Bunch Of Lucent RFTG-m-RB units on eBay ThisMorning!

2006-12-20 Thread Jason Rabel
There was this post a while back for a RFG: http://www.febo.com/pipermail/time-nuts/2005-October/019674.html But I could of sworn I found a more complete pinout elsewhere. I'm about to search through my browser history to see if I can find the other URL(s) with info. Jason > Has anyone got one

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread Jack Hudler
Probably what to take this off list. Eek screen capture. That's one of those heart stoppers on the Win9x platforms, it's got nothing to do with Windows, it the device driver in some of those old cards that CLI (Clear interrupts) for a long period. We had issues with this causing Netware Client's t

[time-nuts] Looking for QST Jan 1990 Article on Crystal S, Q & R testing By DeMaw

2006-12-20 Thread Brooke Clarke
Hi: I'm looking for the subject article on crystal testing, or any other articles on testing crystals. This is more related to knowing if a given crystal is alive than characterizing it, i.e. a Crystal Activity Meter type thing. Have Fun, Brooke Clarke -- w/Java http://www.PRC68.com w/o Jav

Re: [time-nuts] Brooks Shera's GPS locking circuit II

2006-12-20 Thread Brian Kirby
Let me add a note. The Shera controller also has a hold mode. This mode will freeze the DAC output at its current voltage. So when its engaged with a rubidium oscillator, your rubidium becomes a normal unit, except it has been "super tuned" to UTC ! Short term specs return to normal, etc.

Re: [time-nuts] Brooks Shera's GPS locking circuit faults and fixes

2006-12-20 Thread Dr Bruce Griffiths
The phase detector itself in Brooks Shera's GPS locking circuit has several problems: 1) There are no synchronisers so that the partial width pulse response of the counters biases the output. 2) Possible synchronism between the (24MHz) phase measurement clock and the time interval being measur

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Dr Bruce Griffiths
Tom Van Baak wrote: > Hal writes: > >> It might be possible to avoid hanging bridges by dithering >> the sawtooth. I'm thinking of something like a heater under >> the xtal for the GPS unit that gets driven by a medium >> frequency - slow relative to the normal sawtooth but fast >> relative to t

Re: [time-nuts] A Bunch Of Lucent RFTG-m-RB units on eBay This Morning!

2006-12-20 Thread Bill Hawkins
Has anyone got one of these (part number KS24019 L105A) up and running? Is a manual available? Bill Hawkins -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jason Rabel Sent: Wednesday, December 20, 2006 10:58 AM To: 'Discussion of precise time and freq

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Poul-Henning Kamp
In message <[EMAIL PROTECTED]>, "Tom Van Baak" writes: >Warm-up time -- >Many Rb will lock in 5 minutes, typically. Some Qz >take much longer to get on-frequency from cold start. >This can simplify the initial loop locking algorithm. Initial capture is best done with a looser timecons

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread Charles S. Osborne
Lots of good info as always from this list. I probably should mention what some of these PCs are doing. Someone asked about the telescope control PCs. The 26m dishes have their own dedicated GPS receivers for their local time standards. Those do the celestial navigation and tracking via their con

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Didier Juges
In the matter of lifetime (outside of MTBF issues), is it correct that Rb has a built-in life limiting mechanism (the lamp wears out), where Qz does not? If so, Rb oscillators will eventually fail but one might hope a Qz oscillator may not. Didier Tom Van Baak wrote: >> Hello folks, >> >> i li

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Tom Van Baak
> Hello folks, > > i like to play the bad boy again: My claim is > > a) that for most of us a GPSD Rb is of little to no > use compared to a good GPSD xtal oscillator Ulrich, That's a rather general statement, but I understand what you mean. Consider, instead of a bold general assertion which ca

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Ulrich Bangert
Yes, agreed! > -Ursprüngliche Nachricht- > Von: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Im Auftrag von Poul-Henning Kamp > Gesendet: Mittwoch, 20. Dezember 2006 16:43 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] LPRO-101 with Brooks Shera's G

[time-nuts] Obtaining 32768Hz from 10 MHz

2006-12-20 Thread David Forbes
A discussion of driving computer clocks from accurate sources recently came up. While it's true that PCs generally use the CPU clock or the baud rate clock for the timekeeping function, the observation was made that it might be nice to run a standard RTC that uses a 32768 Hz crystal from a 10 M

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread Jack Hudler
The Timer/Clock interrupt is IRQ 0 no other interrupt has a higher priority, therefore this interrupt is rarely missed. If it were missed then interrupts would have to be turned off longer the 110ms (2 times the clock rate) which is an enormous amount of time and due no doubt to an improperly writt

[time-nuts] A Bunch Of Lucent RFTG-m-RB units on eBay This Morning!

2006-12-20 Thread Jason Rabel
Just a heads up, if you search eBay for 'Lucent RFTG' you will see someone has listed a bunch of the rubidium units today with BIN of $130. These are not the previously listed RFG's. The RFTG have the built-in GPS receiver (I think it's a Motorola UT+ or VP), the RFG's do not have the GPS. There's

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread buehl
At 10:25 AM 12/20/2006, you wrote: >Hello folks, > >The controller's task is to always pour just enough fluid from the >second pot into the first pot to keep the fluid level constant despite >the fluid lost through the small hole. One refinement of the model is >that we also consider that the amoun

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Poul-Henning Kamp
In message <[EMAIL PROTECTED]>, "Ulrich Bangert" writes: >a) that for most of us a GPSD Rb is of little to no use compared to a >good GPSD xtal oscillator ... if your hold-over requirement is trivial. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP sin

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Ulrich Bangert
Hello folks, i like to play the bad boy again: My claim is a) that for most of us a GPSD Rb is of little to no use compared to a good GPSD xtal oscillator b) that it is a myth that you may use longer loop time constants with Rb compared to a xtal oscillator Let us first talk about b). It is ne

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread Peter Vince
My information could be out of date, but in the past, the realtime clock only set Windows on bootup. During run windows kept time off the bus crystal (hence the sensitivity to interupts) No matter how cheap, only a defective real time clock will err anything close to 1 minute/day, normal values

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread John Ackermann N8UR
Peter Vince said the following on 12/20/2006 10:11 AM: > I could be talking a lot of hot air, so please forgive me, but I've > had a thought: if PCs still use a Real Time Clock chip, could a hardware > modification be done to give them an accurate clock frequency, rather > than relying on what

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread Peter Vince
I could be talking a lot of hot air, so please forgive me, but I've had a thought: if PCs still use a Real Time Clock chip, could a hardware modification be done to give them an accurate clock frequency, rather than relying on whatever cheap crystal is installed on the mother board? Maybe one

Re: [time-nuts] LPRO-101 with Brooks Shera's GPS locking circuit

2006-12-20 Thread Tom Van Baak
Hal writes: > It might be possible to avoid hanging bridges by dithering > the sawtooth. I'm thinking of something like a heater under > the xtal for the GPS unit that gets driven by a medium > frequency - slow relative to the normal sawtooth but fast > relative to the PLL time constant. This some

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread John Ackermann N8UR
Charles S. Osborne said the following on 12/19/2006 09:02 PM: > I have a query. Does anyone have a favorite network time sync test software? > > Here's my situation. Being at a radio and optical observatory, most > everything we do has varying degrees of time stamp criticality on the stored > data

Re: [time-nuts] PC clock comparison software?

2006-12-20 Thread Hal Murray
> For test purposes I've occassionally set the time server polling > routine to once a day and seen 20 minute errors on delinquent PCs. > Other PCs might stay within a minute. 1 min per day is 694 ppm 20 min per day is 13880 ppm ntpd calls the crystal inaccuracy drift. ntpd can't handle a clock