Re: [time-nuts] 5062C
> There's an HP 5062C closing on eBay soon! > > Corby > Thanks for the heads-up, Corby, even if it incited a bidding war. :) I bought it and got it working without much trouble. The problem turned out to be a resistor that had drifted high and crowbarred the oven-temp shutdown circuit. Its cesium tube is elderly but still has some life in it. Beam current is about 0.47V at the test point (or 10 on the front-panel meter) with the mass-spec voltage at the first peak of 12.0V, and about 0.68V (~12 on the meter) with the mass-spec voltage at its highest peak, at 17.5V. Question: the 5062C manual has some contradictory instructions for setting the mass-spectrometer bias. Page 4-45 says the adjustment is "correct" when the beam current is at its lowest-voltage peak. Page 4-56 says "More than one peak may be indicated... Set MASS SPEC control for highest peak." Which is optimal? In my case I see a lot more beam current at the 17.5V peak than at the 12.0V peak, so I'd rather leave it at 17.5. The bad news is that when I tried installing my spare 5062C Cs tube, which I'd previously bench-tested successfully, the hot-wire ionizer filament opened up at some point during the periodic supply-cycling process that takes place until the ion pump current falls to its normal operating value. That sucked, because now I'll never know how the bench test results compare to actual performance in the clock. I don't see anything I might've done wrong when I installed the other tube. There was just too much O2 in the envelope, I guess... -- john, KE5FX ___ 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] 5062C
John, Is that, now unusable tube a surplus for You? I'd have some use for it... (sectioned, as a display for an University lab).. Predrag Dukic University of Split Croatia At 08:29 23.3.2009, you wrote: > > There's an HP 5062C closing on eBay soon! > > > > Corby > > > >Thanks for the heads-up, Corby, even if it incited a bidding war. :) I >bought it and got it working without much trouble. The problem turned out >to be a resistor that had drifted high and crowbarred the oven-temp shutdown >circuit. > >Its cesium tube is elderly but still has some life in it. Beam current is >about 0.47V at the test point (or 10 on the front-panel meter) with the >mass-spec voltage at the first peak of 12.0V, and about 0.68V (~12 on the >meter) with the mass-spec voltage at its highest peak, at 17.5V. > >Question: the 5062C manual has some contradictory instructions for setting >the mass-spectrometer bias. Page 4-45 says the adjustment is "correct" when >the beam current is at its lowest-voltage peak. Page 4-56 says "More than >one peak may be indicated... Set MASS SPEC control for highest peak." Which >is optimal? In my case I see a lot more beam current at the 17.5V peak than >at the 12.0V peak, so I'd rather leave it at 17.5. > >The bad news is that when I tried installing my spare 5062C Cs tube, which >I'd previously bench-tested successfully, the hot-wire ionizer filament >opened up at some point during the periodic supply-cycling process that >takes place until the ion pump current falls to its normal operating value. >That sucked, because now I'll never know how the bench test results compare >to actual performance in the clock. > >I don't see anything I might've done wrong when I installed the other tube. >There was just too much O2 in the envelope, I guess... > >-- john, KE5FX > > >___ >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] Advanced Crystal Oscillator Design By Benjaminson, A.
Have been looking around for the Technical Reports by Mr Benjaminson that is cited in several oscillator articles(Vig et al), but cant find them. Does any one know where to find these? Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D Technical Report SLCET-TR-85-0445-F, January 1988, AD-B121288; Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D Technical Report SLCET-TR88-0804-1, February 1989, AD-B134514, Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D Technical Report SLCET-TR-88-0804-F, December, 1991 , AD-B163808. Thanks a lot! Anders ___ 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] Advanced Crystal Oscillator Design By Benjaminson, A.
I did a google search on the first one using SLCET-TR-85-0445-F and it appeared to work. I would expect the other document numbers to do the same. Best of luck. Harry, W3IIT == - Original Message - From: "Anders Time" To: Sent: Monday, March 23, 2009 6:00 AM Subject: [time-nuts] Advanced Crystal Oscillator Design By Benjaminson, A. > Have been looking around for the Technical Reports by Mr Benjaminson that > is > cited in several oscillator articles(Vig et al), but cant find them. Does > any one know where to find these? > > Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D > Technical Report SLCET-TR-85-0445-F, January 1988, AD-B121288; > Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D > Technical Report SLCET-TR88-0804-1, February 1989, AD-B134514, > Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D > Technical Report SLCET-TR-88-0804-F, December, 1991 , AD-B163808. > > Thanks a lot! > Anders > ___ > 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] 5062C mass spec. setting
John, Set it for the biggest peak, 17.5V looks to be the one. Corby Digital Photography - Click Now. http://thirdpartyoffers.juno.com/TGL2141/fc/BLSrjpTDvmQS0Oh2LuVYMuNJq4DRE9ltVihQk6NZdYzCLTetZVGTQjA4zHi/ ___ 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] Advanced Crystal Oscillator Design By Benjaminson, A.
Try the NTIS (National Technical Information Service) Anders Time > Have been looking around for the Technical Reports by Mr Benjaminson that > is > cited in several oscillator articles(Vig et al), but cant find them. Does > any one know where to find these? > > Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D > Technical Report SLCET-TR-85-0445-F, January 1988, AD-B121288; > Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D > Technical Report SLCET-TR88-0804-1, February 1989, AD-B134514, > Advanced Crystal Oscillator Design, U. S. Army Laboratory Command R&D > Technical Report SLCET-TR-88-0804-F, December, 1991 , AD-B163808. > > Thanks a lot! > Anders > ___ > 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. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ 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] Datum 9390 Problems
On Mar 22, 00:00 UT, both of our Datum 9390 model GPS receivers/time code generators started producing erroneous day of year and actual year values. Instead of day 81, it said 96 on the front panel, but produced day 196 in the IRIG-B time code. They also reported the year as 2007. The two units are locate 200 miles apart on a remote mountain location and are used to control radio telescopes. The unit on Kitt Peak. Arizona was purchased in 1998 and has a model number of: 9390-6000; Firmware version, I think, of N500/S118/DT101C The Unit on Mt. Graham, Arizona was purchesd around 1995 and is model: 9390-52333; Firmware version: N502/S118/DT300KP. Neither unit has ever undergone a firmware update. I'm pretty sure this may be the root of the problem. Can anyone help me here as Symmetricom doesn't seem interested in answering my tech support calls. Thanks, Tom -- ~~ _/_/_/_/_/_/ _/_/_/_/_/_/ _/_/_/_/_/_/ Thomas W. Folkers _/_/ _/_/ _/_/ Telescope Operations Mgr. _/_/_/_/_/_/ _/_/_/_/_/_/ _/_/ Arizona Radio Observatory _/_/ _/_/ _/_/ Steward Observatory _/_/ _/ _/ _/_/ 933 N. Cherry Ave. Rm. 154 _/_/ _/_/ _/_/_/_/_/_/ Tucson, Arizona 85721 -- email: tfolk...@email.arizona.edu -- Voice: (520) 626-7837 - http://aro.as.arizona.edu/ Fax: (520) 621-5554 Home: (520) 297-5250 --- Cell: (520) 909-1113 ~~ ___ 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] Datum 9390 Problems
Thomas, Thomas Folkers skrev: >On Mar 22, 00:00 UT, both of our Datum 9390 model GPS receivers/time > code generators started producing erroneous day of year and actual year > values. > >Instead of day 81, it said 96 on the front panel, but produced day 196 > in the IRIG-B time code. > >They also reported the year as 2007. > > >The two units are locate 200 miles apart on a remote mountain location > and are used to control radio telescopes. > >The unit on Kitt Peak. Arizona was purchased in 1998 and has a model > number of: > >9390-6000; Firmware version, I think, of N500/S118/DT101C > >The Unit on Mt. Graham, Arizona was purchesd around 1995 and is model: > >9390-52333; Firmware version: N502/S118/DT300KP. > >Neither unit has ever undergone a firmware update. I'm pretty sure > this may be the root of the problem. > > >Can anyone help me here as Symmetricom doesn't seem interested in > answering my tech support calls. I got a call from a friend that had a call from one of his customers that had all their receiver fail in the same fashion. Their Symmetricom receivers however reverted back to an older date. I will try to get the details. My conclusion is that it is a bad 1024-week wrapping routine in action. The lack of firmware upgrade is most certainly the root cause as the typical way to resolve it is to use a reference date near time of first shipping as reference and then calculate away from that. Unless you get firmware upgrades your receivers have just become a piece of junk and you are expected to buy new... So, you are not alone with this problem. The lack of firmware upgrades that handles dates and signal upgrades (such as PRN 31 and PRN 32) is a constant source of GPS failures. It also has a very scary tendency to be coordinated. GPS receivers older than 10 years should maybe not be kept in production unless it is known to work and be sufficiently supported. So, I got one of those "I told you so" moments today. Cheers, Magnus ___ 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] 5062C
> John, > > Is that, now unusable tube a surplus for You? I'd have some use > for it... > > (sectioned, as a display for an University lab).. > > > Predrag Dukic > University of Split > Croatia Sure, Predrag, you're welcome to it. Someone might as well get some use out of it. Send me your address offline to jmi...@pop.net, and I'll put it on the slow boat. I'm sure you know to be careful opening the tube up, as cesium is nasty stuff. -- john, KE5FX ___ 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] Datum 9390 Problems
> -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on > Behalf Of Thomas Folkers > Sent: Monday, March 23, 2009 12:11 PM > To: time-nuts@febo.com > Subject: [time-nuts] Datum 9390 Problems > > > >On Mar 22, 00:00 UT, both of our Datum 9390 model GPS receivers/time > code generators started producing erroneous day of year and actual year > values. > Same here, it's day "597" according to my Datum 9390 Rb clock. The time appears correct. Also interesting is the 10 MHz output, which appears to be about 2E-10 high compared to a Thunderbolt and cesium standard. That wasn't the case when I first bought the 9390 a year or so ago, but it's been true for at least a couple of days now. There's no indication in the display that the rubidium's unlocked, as the status remains "Doing GPS correction (System check OK)". Anyone else seeing a constant frequency error from theirs? -- john, KE5FX ___ 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] Datum 9390 Problems
- Original Message - From: "Thomas Folkers" To: Sent: Monday, March 23, 2009 3:10 PM Subject: [time-nuts] Datum 9390 Problems > > On Mar 22, 00:00 UT, both of our Datum 9390 model GPS receivers/time > code generators started producing erroneous day of year and actual year > values. > Symmetricom could care less, no, in fact they are rather happy as they would like all that old equipment to be buried. Firmware for that vintage is out of the question now. It is my understanding that newer receiver boards solved that issue. My question, could some newer generic receiver module be programmed/interfaced to replace that board? I don't have a component level manual on that receiver. I too have a couple of those units that we use simply for the disciplined rubidium 10 meg out even though the week and year is and has been off for some time. Phil ___ 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] Heath Most Accurate Clock
I don't know the mailing list "rules". I have a Most Accurate Clock (GC-1000H) to sell, has two manuals and RS-232 interface. Receivers work and they switch, but the data led does not blink much. It was working but I now have GPS timing, so will let it go. If you're interested, I'll sell for $250 + $10 s/h. Will go on $%^# if no-one here wants it. If this offering is in bad taste, please excuse (if it tastes bad, nothing I can do...). Don -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com ___ 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] Datum 9390 Problems
On Mon, Mar 23, 2009 at 04:17:00PM -0400, phil wrote: > Firmware for that vintage is out of the question now. It is my understanding > that newer receiver boards solved that issue. My question, could some newer > generic receiver module be programmed/interfaced to replace that board? I > don't have a component level manual on that receiver. I have a 9390 with Rb - currently in deep retirement - that I acquired in 2000. It locked OK after I repaired the 16.368 MHz oscillator lock circuit, but had the rollover date problem. I eventually was given a small PIC microcontroller based adapter card from a defunct 9390 someone else owned that went between the Trimble GPS board and the Datum mother board and fiddled the serial data messages from the GPS to correct the GPS date (as I remember it, it added the leading 1024 bit in a 16 bit field). This corrected the date so it read correctly. This Datum mini board was apparently at least one of the fixes that Datum provided customers for the GPS date rollover bug - there may also have been some updated firmware for the motherboard, I forget. I did disassemble the PIC code, but what I did with the results I forget... other than decide what the board did to the data stream. I did have a copy of the schematic and a user manual for the Datum 9390 I got from Symetricomm/Datum - this definitely did NOT include much info on the Trimble GPS board and as I remember it the manual didn't match the firmware I had all that well nor did the schematic match the hardware I had exactly either. Eventually the DC to DC converter potted module died, and unable to locate a drop in replacement I retired the 9390 in favor of a couple of HP 58540as and then Trimble Thunderbolts and a Datum PRR-10 disciplined Rb clock with LPRO Rbs. The 9390 had a rather dirty high PN 10 and 5 MHz output which was another problem I never quite got around to solving. > > I too have a couple of those units that we use simply for the disciplined > rubidium 10 meg out even though the week and year is and has been off for > some time. > Phil I guess it is time to look up the GPS date in weeks and see how close to the next rollover it is... -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ 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] Datum 9390 Problems
David, David I. Emery skrev: > On Mon, Mar 23, 2009 at 04:17:00PM -0400, phil wrote: >> Firmware for that vintage is out of the question now. It is my understanding >> that newer receiver boards solved that issue. My question, could some newer >> generic receiver module be programmed/interfaced to replace that board? I >> don't have a component level manual on that receiver. > > > I have a 9390 with Rb - currently in deep retirement - that I > acquired in 2000. It locked OK after I repaired the 16.368 MHz oscillator > lock circuit, but had the rollover date problem. What magical GPS week number did we just hit? http://www.ngs.noaa.gov/CORS/Gpscal.html The time of failure matches the entering of GPS week 1524. This is an interesting number as it is exactly 1024 + 500. 500 seems like an fairly arbitrary GPS week number to use as a base number. It matches... 1989-08-06: http://csrc.ucsd.edu/scripts/convertDate.cgi?time=0500+0 So the magic GPS week roll-over bias is now known for these. > I eventually was given a small PIC microcontroller based adapter > card from a defunct 9390 someone else owned that went between the Trimble > GPS board and the Datum mother board and fiddled the serial data > messages from the GPS to correct the GPS date (as I remember it, it > added the leading 1024 bit in a 16 bit field). This corrected the date > so it read correctly. > > This Datum mini board was apparently at least one of the fixes > that Datum provided customers for the GPS date rollover bug - there may > also have been some updated firmware for the motherboard, I forget. Strange option to make a separate board rather than modify the firmware. > I did disassemble the PIC code, but what I did with the results > I forget... other than decide what the board did to the data stream. > > I did have a copy of the schematic and a user manual for the Datum > 9390 I got from Symetricomm/Datum - this definitely did NOT include much > info on the Trimble GPS board and as I remember it the manual didn't > match the firmware I had all that well nor did the schematic match > the hardware I had exactly either. Wohooo! >> I too have a couple of those units that we use simply for the disciplined >> rubidium 10 meg out even though the week and year is and has been off for >> some time. >> Phil > > I guess it is time to look up the GPS date in weeks and see how > close to the next rollover it is... > Can be any week now... but week 1536 (1024 + 512) seems like a likely arbitrary week like anyone... Maybe it is time for me to get a GPS L1 tester... Cheers, Magnus ___ 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] 5062C
Um, John. Cesium is a Haz Mat. Are you prepared for all the export paperwork to do the shipment? Dave - Original Message - From: "John Miles" To: "Discussion of precise time and frequency measurement" Sent: Monday, March 23, 2009 12:53 PM Subject: Re: [time-nuts] 5062C > John, > > Is that, now unusable tube a surplus for You? I'd have some use > for it... > > (sectioned, as a display for an University lab).. > > > Predrag Dukic > University of Split > Croatia Sure, Predrag, you're welcome to it. Someone might as well get some use out of it. Send me your address offline to jmi...@pop.net, and I'll put it on the slow boat. I'm sure you know to be careful opening the tube up, as cesium is nasty stuff. -- john, KE5FX ___ 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] 5062C
No but that's a good question, now that USPS no longer offers a surface-delivery option. Are there special forms that need to be filled out when shipping these things by air? The tube originally came via air from Australia with no special labelling. -- john, KE5FX > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on > Behalf Of Dave Carlson > Sent: Monday, March 23, 2009 3:25 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] 5062C > > > Um, John. Cesium is a Haz Mat. Are you prepared for all the export > paperwork to do the shipment? > > Dave > - Original Message - > > From: "John Miles" > To: "Discussion of precise time and frequency measurement" > > Sent: Monday, March 23, 2009 12:53 PM > Subject: Re: [time-nuts] 5062C > > > > > John, > > > > Is that, now unusable tube a surplus for You? I'd have some use > > for it... > > > > (sectioned, as a display for an University lab).. > > > > > > Predrag Dukic > > University of Split > > Croatia > > Sure, Predrag, you're welcome to it. Someone might as well get > some use out > of it. Send me your address offline to jmi...@pop.net, and I'll put it on > the slow boat. > > I'm sure you know to be careful opening the tube up, as cesium is nasty > stuff. > > -- john, KE5FX > > > > ___ > 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] 5062C
Someone on the list mentioned that Cesium tubes are exempt (well contained, small quantity) Predrag At 23:47 23.3.2009, you wrote: >No but that's a good question, now that USPS no longer offers a >surface-delivery option. Are there special forms that need to be filled out >when shipping these things by air? > >The tube originally came via air from Australia with no special labelling. > >-- john, KE5FX > > > -Original Message- > > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on > > Behalf Of Dave Carlson > > Sent: Monday, March 23, 2009 3:25 PM > > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] 5062C > > > > > > Um, John. Cesium is a Haz Mat. Are you prepared for all the export > > paperwork to do the shipment? > > > > Dave > > - Original Message - > > > > From: "John Miles" > > To: "Discussion of precise time and frequency measurement" > > > > Sent: Monday, March 23, 2009 12:53 PM > > Subject: Re: [time-nuts] 5062C > > > > > > > > > John, > > > > > > Is that, now unusable tube a surplus for You? I'd have some use > > > for it... > > > > > > (sectioned, as a display for an University lab).. > > > > > > > > > Predrag Dukic > > > University of Split > > > Croatia > > > > Sure, Predrag, you're welcome to it. Someone might as well get > > some use out > > of it. Send me your address offline to jmi...@pop.net, and I'll put it on > > the slow boat. > > > > I'm sure you know to be careful opening the tube up, as cesium is nasty > > stuff. > > > > -- john, KE5FX > > > > > > > > ___ > > 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] Datum 9390 Problems
On Mon, Mar 23, 2009 at 11:23:35PM +0100, Magnus Danielson wrote: > > This Datum mini board was apparently at least one of the fixes > > that Datum provided customers for the GPS date rollover bug - there may > > also have been some updated firmware for the motherboard, I forget. > > Strange option to make a separate board rather than modify the firmware. I think the intent was to supply upgraded Trimble GPS receiver cards eventually (or firmware for the existing one, which presumably comes from Trimble) and this fix allowed the old unmodified GPS board and the little PIC thingy to work with the same Datum firmware that would also handle an upgraded receiver with more bits in its GPS week output. Maybe some Trimble receiver boards exist that do supply the additional bits - it is not known to me if all 9390s which were upgraded used this particular fix. -- Dave Emery N1PRE/AE, d...@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either." ___ 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] 5062C
see http://www.agilent.com/metrology/hazardous.shtml Brian KD4FM Dave Carlson wrote: > Um, John. Cesium is a Haz Mat. Are you prepared for all the export > paperwork to do the shipment? > > Dave > - Original Message - > > From: "John Miles" > To: "Discussion of precise time and frequency measurement" > > Sent: Monday, March 23, 2009 12:53 PM > Subject: Re: [time-nuts] 5062C > > > > >> John, >> >> Is that, now unusable tube a surplus for You? I'd have some use >> for it... >> >> (sectioned, as a display for an University lab).. >> >> >> Predrag Dukic >> University of Split >> Croatia >> > > Sure, Predrag, you're welcome to it. Someone might as well get some use out > of it. Send me your address offline to jmi...@pop.net, and I'll put it on > the slow boat. > > I'm sure you know to be careful opening the tube up, as cesium is nasty > stuff. > > -- john, KE5FX > > > > ___ > 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] 5062C
Hmm, looks like there is no problem for domestic shipments but some potential red tape for international shipments. Predrag, I'll look into it a bit and let you know offline if it appears to be feasible to ship it to you. -- john, KE5FX > -Original Message- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on > Behalf Of Brian Kirby > Sent: Monday, March 23, 2009 5:28 PM > To: Dave Carlson; Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] 5062C > > > see http://www.agilent.com/metrology/hazardous.shtml > > Brian KD4FM > > Dave Carlson wrote: > > Um, John. Cesium is a Haz Mat. Are you prepared for all the export > > paperwork to do the shipment? > > > > Dave > ___ 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.
