Re: [time-nuts] AN/URQ-10A
I can say inners always take a lot longer The battery pack being out may be effecting some critical voltage Just a guess Paul WB8TSL On Fri, Apr 26, 2013 at 5:07 PM, engineer...@mt.net wrote: To all, I acquired a AN/URQ-10A frequency standard which appears to have received little or no service since its birth. There are no signs of ever being mounted in its mating rack and the unit has virtually no scratches or wear marks on it. Last night I finally managed to plug it in to see how it behaved. Obviously the D NiCads in the battery module were flat and need replacement so I left the battery module out of the unit. As expected, the unit powered up with all normal indications on the meter except for the outer and inner ovens. After about three hours the indication for the outer oven became normal but after four hours I still did not have any indication on the inner oven reading. By that time my pillow was calling me so I unplugged the unit to wait for further investigation fearing that if the heater was stuck full on, internal heat damage may result (if it hasn't already). But I did witness one observation that the inner oven meter indication briefly tweaked as the power supply was shutting down telling me that the heater element itself has continuity. This told me that the heater was probably hot and when the power went down, the control circuitry shut the heater drive transistor off (don't know if anyone has observed the design of the metering circuit in this thing but the meter is connected between the heater and the collector of the drive transistor. When cold, the transistor is fully conducting thereby pulling this point to ground. As the temperature reaches equilibrium, this point then become positive as the drive transistor starts to reduce conduction. The meter then sees a voltage at this point and indicates proper heater operation). Question #1: Does anyone have an idea as to how long one should wait to see an indication of inner oven operation? Given the time it took for the outer oven to come up, do I need more patience? Comment/question #2: I did download the schematics for the URQ-10 (not A version) from the febo website but after a little disassembly and from obvious indication of additional controls on the non-A URQ-10 schematics, this A version is a horse of a different color. A diligent search of the Internet has produced no results of information on the A version except for one original NAVSHIPS OP/SVC manual for it that went on eBay a little while ago (drats!). Comment/question #3: Not investing any additional time last night (sleep required), I simply tapped on the FE-10 oscillator module enclosure and found it to be as solid as a rock. I don't have time to do more peeking at present but assume that this is due to (what I believe) is a Dewar enclosure that is contained inside. Correct? If the inner oven has cratered, is the internal oven control circuitry contained in this enclosure accessible by any means or is it sealed forever? This unit may be old but it is certainly near collector status with regards to its physical condition. Any help, especially schematics, would be appreciated. Regards, Greg Muir --**--** This message was sent using IMP, the Internet Messaging Program. __**_ 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.
Re: [time-nuts] HP5065B !!!
Hi, Where are the details of the changes and how to do them? Jim On Saturday, 27 April 2013, John Miles wrote: Very nice bit of RD work on Corby's part. Mine is certainly working well after the modification, but I'm just blown away at the performance seen with Tom's unit. Another plot of the Super mod that's worth mentioning: http://www.ke5fx.com/5065A_vs_maser_mask.png Below 1000 seconds it has no trouble passing the spec limits for a passive H-maser! For contrast, teeypical LPRO-101 performance is shown in green, and the red trace is from the second-best commercial Rb standard I've seen (Symmetricom XPRO). -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts-boun...@febo.com javascript:; [mailto:time-nuts-javascript:; boun...@febo.com javascript:;] On Behalf Of cdel...@juno.comjavascript:; Sent: Friday, April 26, 2013 8:24 AM To: time-nuts@febo.com javascript:; Subject: [time-nuts] HP5065B !!! OK, that was just to get your attention! What do you call a modified HP 5065A that can give you an Allan Deviation of 4X10-13 @ 1 Second and 6X10-14 @ 100 Second? I call it the SUPER HP 5065A. Any of these links will get you to the document describing it. Have a look and see what it's all about! Enjoy, Corby http://leapsecond.com/corby/Super-5065A-Project.pdf or http://leapsecond.com/corby/superproj10.docx or http://www.febo.com/pages/HP5065A_SUPER for ___ time-nuts mailing list -- time-nuts@febo.com javascript:; 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 javascript:; 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] HP5065B !!!
Very nice bit of RD work on Corby's part. Mine is certainly working well after the modification, but I'm just blown away at the performance seen with Tom's unit. Hi John, Yes, apparently some 5065A respond better than others to Corby's clever mod. It's clear why there is improvement; it's an interesting challenge/mystery to understand why some get more improvement than others. I double checked its performance with both a TSC 5110A/5120A and your TimePod to be sure it wasn't me. In general, some HP 5065A are better than others. OTOH, this is somewhat true for any frequency standard: from pendulum to quartz to rubidium to cesium to hydrogen. It drives time nuts crazy (and turns some of us into eBay gold diggers) but this has been the case from the first hand-made quartz oscillators in the 1920's to, well, the hand-made GPS Rubidium's, or the hand-made cesium fountains of today. Every clock is slightly different. You can be practical and live with it, or a fanatic and keep searching for a slightly better one or finding out why and putting effort into tweaking parameters, swapping components, or boards, etc. I know Corby has done an amazing job over the years with vintage cesium and rubidium standards. I hope to have him upgrade some of my 5065A too. Just to clarify -- the excellent plot that Corby posted was a modified 5065A that I tested *for* him, not one that I actually own. So it's not Tom's unit, but one that Tom enjoyed testing. Note the baseline was a PHM vs. AHM, just to show the noise floor of the measurement system(s) and reference(s). /tvb Another plot of the Super mod that's worth mentioning: http://www.ke5fx.com/5065A_vs_maser_mask.png Below 1000 seconds it has no trouble passing the spec limits for a passive H-maser! For contrast, teeypical LPRO-101 performance is shown in green, and the red trace is from the second-best commercial Rb standard I've seen (Symmetricom XPRO). -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts- boun...@febo.com] On Behalf Of cdel...@juno.com Sent: Friday, April 26, 2013 8:24 AM To: time-nuts@febo.com Subject: [time-nuts] HP5065B !!! OK, that was just to get your attention! What do you call a modified HP 5065A that can give you an Allan Deviation of 4X10-13 @ 1 Second and 6X10-14 @ 100 Second? I call it the SUPER HP 5065A. Any of these links will get you to the document describing it. Have a look and see what it's all about! Enjoy, Corby http://leapsecond.com/corby/Super-5065A-Project.pdf or http://leapsecond.com/corby/superproj10.docx or http://www.febo.com/pages/HP5065A_SUPER for ___ 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] nanobsd conf
Hi All, I am trying to get my head around building a nanobsd for some HP thinclients to run as stratum 1 servers. If you have the time, please send me an example conf file for sh nanobsd.sh -c myconf.nano I am unsure of how to add my 2 refclocks, a 29 (trimble) and a 20 (nmea+pps) Also, where do I add PPS to the kernel options? Many tahnks, mark ___ 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] AN/URQ-10A frequency standard
Thank you for you replies Dave and Paul! Well, patience won out and I left the unit on for a considerably longer time. The inner oven meter indication then started to come up off of zero after nearly seven hours. Not knowing the thermal mass it has to heat I guess I assumed that it would have a slightly quicker response time. My ignorance... This morning I checked the unit again and the inner oven indication is slightly lower than where it should be in the red OK region on the meter meaning that the heater is still delivering a little more than normal heat and the 5 MHz frequency, which started out at ~+33 Hz cold, is now at -1.2 Hz and holding steady telling me that the heat delivered has overshot its normal operating point. Granted I have not let the crystal assembly soak for any considerable time but my mind is thinking about a possible bias in the heater control circuit by a leaky passive component or transistor causing it to remain on a little more than necessary. But, again, I will be patient and watch its progress over the upcoming days. I pulled out a Sulzer 5A manual and took a closer look at the schematic. From what I observed in the URQ-10 circuitry that is external to the FE-10 oscillator itself, the power supply and frequency handling portions appear to come close to nearly a carbon copy of the older Sulzer unit. The non-A version URQ-10 design is considerably different and somewhat more complex. And if anyone out there comes across an A version manual or has one in their possession, I would be willing to compensate them for a photocopy. Regards, Greg ___ 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] OT - but of interest?
On Fri, 26 Apr 2013 17:59:21 -0700, Jim Lux wrote: Total dose will be very small (after all astronauts live in LEO) So you'd worry about cosmic rays and single event effects. snip They fly a lot of unmodified commercial equipment on ISS (and on Shuttle, when we still flew it) and they typically have MTBF of a month or so for the really soft parts. Most stuff will last a year before it dies. snip I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. Greg ___ 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] OT - but of interest?
When I was building space payloads, every component had to meet or exceed a VCM (Volitile Condensible Material) spec. This was mainly of concern with plastics, like wire insulation (we used Teflon and Kapton) but especially potting compounds. And, don't even think about ball bearings near optics in scanners!! -John I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. Greg ___ 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] AN/URQ-10A frequency standard
I looked and must have hit the same site you did for the sulzer. Yes I expect a log warmup. I used them in the navy and we never let them go cold. circa 1973-1979. Took them to the cal lab on battery etc. I thought maybe I would have a manual I don't. You are lucky to get one. Great reference. I do have two model 5a sulzers. I actually use one to generate the lab frequencies for stuff. I really should put it back together which I can do and just create a more modern divider. That would consume less power and be equally clean also take less space. 1 RU. Regards Paul WB8TSL On Sat, Apr 27, 2013 at 12:21 PM, Gregory Muir engineer...@mt.net wrote: Thank you for you replies Dave and Paul! Well, patience won out and I left the unit on for a considerably longer time. The inner oven meter indication then started to come up off of zero after nearly seven hours. Not knowing the thermal mass it has to heat I guess I assumed that it would have a slightly quicker response time. My ignorance... This morning I checked the unit again and the inner oven indication is slightly lower than where it should be in the red OK region on the meter meaning that the heater is still delivering a little more than normal heat and the 5 MHz frequency, which started out at ~+33 Hz cold, is now at -1.2 Hz and holding steady telling me that the heat delivered has overshot its normal operating point. Granted I have not let the crystal assembly soak for any considerable time but my mind is thinking about a possible bias in the heater control circuit by a leaky passive component or transistor causing it to remain on a little more than necessary. But, again, I will be patient and watch its progress over the upcoming days. I pulled out a Sulzer 5A manual and took a closer look at the schematic. From what I observed in the URQ-10 circuitry that is external to the FE-10 oscillator itself, the power supply and frequency handling portions appear to come close to nearly a carbon copy of the older Sulzer unit. The non-A version URQ-10 design is considerably different and somewhat more complex. And if anyone out there comes across an A version manual or has one in their possession, I would be willing to compensate them for a photocopy. Regards, Greg ___ 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] OT - but of interest?
On Sat, Apr 27, 2013 at 9:40 AM, Gregory Muir engineer...@mt.net wrote: I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. I went to a lecture on the idea of putting a cell phone like object in orbit. The idea was that it should have a cost and size about like a phone. This is very different from a pico-sat (a 4 inch cube) because the pico sat costs $100,000 or more and the phone is under $500 The idea is that $500 satellites you don't have to care about failures. The plan was to place maybe 100,000 devices in orbit and as they fail just launch another 1,000 or so at a time. The proposal was to launch them from a rocket carried under an aircraft. The goal was an un-jamable world wide data network. The phones would self-organize into a mesh network. But no one is going to do this. But still the question lives on: What could you do with a iPhone in orbit? One idea was diagnostics. A big spacecraft like a space station of crew capsule headed to mars might toss a few outside so they could get photos of the exterior if they suspected a problem or if the phone is cheap just to get snapshot. But I'd bet a bunch they'd use a $100K pico sat for that. -- 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.
[time-nuts] Sulzer 5A battery replacement
Fellow time-nuts, I have a Sulzer 5A, but no NiCd batteries. Buying new batteries is possible, but would cost me more than the unit cost me. One alternative proposed would be to build a Zener-based battery-simulator, to have the PSU operate properly without batteries. Another would be to fit other batteries for which the PSU would be able to charge and maintain. I'm open to constructive suggestions. As it is right now, I can't really operate it even. 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] OT - but of interest?
Hi Chris, On 04/27/2013 11:07 PM, Chris Albertson wrote: On Sat, Apr 27, 2013 at 9:40 AM, Gregory Muirengineer...@mt.net wrote: I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. I went to a lecture on the idea of putting a cell phone like object in orbit. The idea was that it should have a cost and size about like a phone. This is very different from a pico-sat (a 4 inch cube) because the pico sat costs $100,000 or more and the phone is under $500 The idea is that $500 satellites you don't have to care about failures. The plan was to place maybe 100,000 devices in orbit and as they fail just launch another 1,000 or so at a time. The proposal was to launch them from a rocket carried under an aircraft. The trouble I see with that approach would be that their failure rate would be rather high starting at about the same time, the launch, so the launch rate must be high enough to maintain service. Also, you would like to do some basic protection scheme on each phone for them not to fail completely, as I suspect that temperature gradients isn't ideal of them. This means that the price per phone goes up and also, the price of each launch is relevant. The total weight is also a factor, as it controls the number of devices that can be launched, and hence the failure rate statistics to maintain service until the last one dies. A failure of this discussion is the lack of synchronisation or even syntonization of these devices, or at least transmission of time signals... 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] OT - but of interest?
Putting 100,000 items in space is a non-starter. The existing space trash is already a big concern, and there have been seriuous proposals for missions to clean it up. An iPhone, travelling at orbital velocity, has a lot of kinetic energy! There was an uproar years ago when the Westford Needles experiment was launched, and those had a known mechanism to de-orbit the things. As to tossing one out the docking port, unstabilized objects will tumble. The chances of getting a useful picture of the area of interest are small. YMMV, -John == On Sat, Apr 27, 2013 at 9:40 AM, Gregory Muir engineer...@mt.net wrote: I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. I went to a lecture on the idea of putting a cell phone like object in orbit. The idea was that it should have a cost and size about like a phone. This is very different from a pico-sat (a 4 inch cube) because the pico sat costs $100,000 or more and the phone is under $500 The idea is that $500 satellites you don't have to care about failures. The plan was to place maybe 100,000 devices in orbit and as they fail just launch another 1,000 or so at a time. The proposal was to launch them from a rocket carried under an aircraft. The goal was an un-jamable world wide data network. The phones would self-organize into a mesh network. But no one is going to do this. But still the question lives on: What could you do with a iPhone in orbit? One idea was diagnostics. A big spacecraft like a space station of crew capsule headed to mars might toss a few outside so they could get photos of the exterior if they suspected a problem or if the phone is cheap just to get snapshot. But I'd bet a bunch they'd use a $100K pico sat for that. -- 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. ___ 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] OT - but of interest?
Gentlemen, One of the objects of the phone sat missions is to ensure deorbit for exactly that reason. (As a matter of fact, it just happened today.) More than a few of the new cubesats have deployable streamers to accelerate reentry. Why not a cloud of 100? Start small. Makes sense and sounds good. 73 de Norm n3ykf On Sat, Apr 27, 2013 at 7:03 PM, J. Forster j...@quikus.com wrote: Putting 100,000 items in space is a non-starter. The existing space trash is already a big concern, and there have been seriuous proposals for missions to clean it up. An iPhone, travelling at orbital velocity, has a lot of kinetic energy! There was an uproar years ago when the Westford Needles experiment was launched, and those had a known mechanism to de-orbit the things. As to tossing one out the docking port, unstabilized objects will tumble. The chances of getting a useful picture of the area of interest are small. YMMV, -John == On Sat, Apr 27, 2013 at 9:40 AM, Gregory Muir engineer...@mt.net wrote: I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. I went to a lecture on the idea of putting a cell phone like object in orbit. The idea was that it should have a cost and size about like a phone. This is very different from a pico-sat (a 4 inch cube) because the pico sat costs $100,000 or more and the phone is under $500 The idea is that $500 satellites you don't have to care about failures. The plan was to place maybe 100,000 devices in orbit and as they fail just launch another 1,000 or so at a time. The proposal was to launch them from a rocket carried under an aircraft. The goal was an un-jamable world wide data network. The phones would self-organize into a mesh network. But no one is going to do this. But still the question lives on: What could you do with a iPhone in orbit? One idea was diagnostics. A big spacecraft like a space station of crew capsule headed to mars might toss a few outside so they could get photos of the exterior if they suspected a problem or if the phone is cheap just to get snapshot. But I'd bet a bunch they'd use a $100K pico sat for that. -- 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. ___ 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] Sulzer 5A battery replacement
I just built a 3 term adjustable reg and that was it. Been running fine for many many years. Pretty sure this topic has been on time-nuts before and as I recall the 3 terminal regulator was a completely evil solution. That discussion was a while ago also. In the meantime as look to the right and in the rack its running just fine. Regards Paul WB8TSL On Sat, Apr 27, 2013 at 6:47 PM, Magnus Danielson mag...@rubidium.dyndns.org wrote: Fellow time-nuts, I have a Sulzer 5A, but no NiCd batteries. Buying new batteries is possible, but would cost me more than the unit cost me. One alternative proposed would be to build a Zener-based battery-simulator, to have the PSU operate properly without batteries. Another would be to fit other batteries for which the PSU would be able to charge and maintain. I'm open to constructive suggestions. As it is right now, I can't really operate it even. Cheers, Magnus __**_ 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.
Re: [time-nuts] OT - but of interest?
An iPhone as a weapon of mass (times velocity squared) destruction. On 4/27/2013 7:03 PM, J. Forster wrote: Putting 100,000 items in space is a non-starter. The existing space trash is already a big concern, and there have been seriuous proposals for missions to clean it up. An iPhone, travelling at orbital velocity, has a lot of kinetic energy! There was an uproar years ago when the Westford Needles experiment was launched, and those had a known mechanism to de-orbit the things. As to tossing one out the docking port, unstabilized objects will tumble. The chances of getting a useful picture of the area of interest are small. YMMV, -John == On Sat, Apr 27, 2013 at 9:40 AM, Gregory Muir engineer...@mt.net wrote: I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. I went to a lecture on the idea of putting a cell phone like object in orbit. The idea was that it should have a cost and size about like a phone. This is very different from a pico-sat (a 4 inch cube) because the pico sat costs $100,000 or more and the phone is under $500 The idea is that $500 satellites you don't have to care about failures. The plan was to place maybe 100,000 devices in orbit and as they fail just launch another 1,000 or so at a time. The proposal was to launch them from a rocket carried under an aircraft. The goal was an un-jamable world wide data network. The phones would self-organize into a mesh network. But no one is going to do this. But still the question lives on: What could you do with a iPhone in orbit? One idea was diagnostics. A big spacecraft like a space station of crew capsule headed to mars might toss a few outside so they could get photos of the exterior if they suspected a problem or if the phone is cheap just to get snapshot. But I'd bet a bunch they'd use a $100K pico sat for that. -- 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. ___ 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. - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1432 / Virus Database: 3162/5777 - Release Date: 04/27/13 ___ 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] OT - but of interest?
On Sat, 27 Apr 2013 12:06:45 -0700 (PDT), L. Forster wrote: When I was building space payloads, every component had to meet or exceed a VCM (Volitile Condensible Material) spec. This was mainly of concern with plastics, like wire insulation (we used Teflon and Kapton) but especially potting compounds. And, don't even think about ball bearings near optics in scanners!! -John Most of our payloads revolved around high-resolution optics including high dispersion spectrographs. Mechanical items were either verboten or encountered serious design reviews that frequently made you put your optics in a separate container. Even with space QPL'd parts, I would be amazed at the goop that the techs would clean out of the vacuum tunnel diffusion pump traps at the end of the test cycles from all of the compounds that migrated into them. Greg ___ 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] AN/URQ-10A frequency standard
On Sat, 27 Apr 2013 16:16:17 -0400, Paul Swed wrote: I looked and must have hit the same site you did for the sulzer. Yes I expect a log warmup. I used them in the navy and we never let them go cold. circa 1973-1979. Took them to the cal lab on battery etc. I thought maybe I would have a manual I don't. You are lucky to get one. Great reference. I do have two model 5a sulzers. I actually use one to generate the lab frequencies for stuff. I really should put it back together which I can do and just create a more modern divider. That would consume less power and be equally clean also take less space. 1 RU. Regards Paul WB8TSL These are neat little machines. But this one is still sticking to it's abnormal inner oven temp and is not moving. I'll let it cook a little longer then may have to do some invasive diagnostics. I keep an odd assortment of whatever-I-can-find oscillators around the lab for use as external time base clocks for frequency counters that I use to look at frequency offsets in stabilized light sources by heterodyning their outputs against a calibrated optical source to generate more easily measured RF products in the microwave range. I'm hoping this little guy will start to show its stuff soon. Greg ___ 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] OT - but of interest?
Sometimes imaging sensors are just not available at wavelengths of interest. There is no choice but mechanical scanners. Bearings are also needed to de-spin antennas, etc. -John = On Sat, 27 Apr 2013 12:06:45 -0700 (PDT), L. Forster wrote: When I was building space payloads, every component had to meet or exceed a VCM (Volitile Condensible Material) spec. This was mainly of concern with plastics, like wire insulation (we used Teflon and Kapton) but especially potting compounds. And, don't even think about ball bearings near optics in scanners!! -John Most of our payloads revolved around high-resolution optics including high dispersion spectrographs. Mechanical items were either verboten or encountered serious design reviews that frequently made you put your optics in a separate container. Even with space QPL'd parts, I would be amazed at the goop that the techs would clean out of the vacuum tunnel diffusion pump traps at the end of the test cycles from all of the compounds that migrated into them. Greg ___ 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] OT - but of interest?
On 4/27/13 9:40 AM, Gregory Muir wrote: On Fri, 26 Apr 2013 17:59:21 -0700, Jim Lux wrote: Total dose will be very small (after all astronauts live in LEO) So you'd worry about cosmic rays and single event effects. snip They fly a lot of unmodified commercial equipment on ISS (and on Shuttle, when we still flew it) and they typically have MTBF of a month or so for the really soft parts. Most stuff will last a year before it dies. snip I'm curious if they ever have any problem with earth-based commercial component outgassing clouding the camera optics. I suspect that on ISS, there's no precision imaging. There's so much crud flying around station I doubt it would be worth trying. Station is a unique environment. It's enormous (100 meters), it's mind bendingly complex (no single person understands it, there's thousands of people involved). Another problem with doing any sort of precision imaging is that you probably don't know where your sensor is or where it's pointed with sufficient precision. In absolute terms, you probably know where it is within about 100 meters (in Earth referenced coordinates) and where it's pointed within a few degrees. The structure moves and flexes a lot. No spy satellite here.. We're doing a precision orbit determination experiment with a software GPS receiver over the next few months (it is the first civil L1/L2c/L5 GPS receiver in orbit). It's been challenging to find out information like Center of Mass position, where the other GPS receivers are, etc. (complicated in part because half of station is measured in inches/feet, and the other half in meters) I ___ 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] AN/URQ-10A frequency standard
Gregory Well I am afraid I have become spoiled in that I use the GPS locked references these days. They consume little power or maybe about the same actually as the 10. So I also have a mix of great old oscillators. But for me at least thats what the 10 would be. I have to say that it was what started me on the ole time-nuttery way back when I had to adjust our shipboard radios to the reference incase they ever failed or... Though at that point I don't think radios would have been on my mind. I had looked for them at hamfests over the years the closest I came was some apha grade urq 11,12, or 13 from Frequency Electronics. Anyhow its never ever worked right at the core. And thats why it was at the hamfest. I did not pay much for it so can't actually complain. You don't really see much of that stuff anymore. Good luck on the inner oven. Regards Paul. On Sat, Apr 27, 2013 at 8:33 PM, Gregory Muir engineer...@mt.net wrote: On Sat, 27 Apr 2013 16:16:17 -0400, Paul Swed wrote: I looked and must have hit the same site you did for the sulzer. Yes I expect a log warmup. I used them in the navy and we never let them go cold. circa 1973-1979. Took them to the cal lab on battery etc. I thought maybe I would have a manual I don't. You are lucky to get one. Great reference. I do have two model 5a sulzers. I actually use one to generate the lab frequencies for stuff. I really should put it back together which I can do and just create a more modern divider. That would consume less power and be equally clean also take less space. 1 RU. Regards Paul WB8TSL These are neat little machines. But this one is still sticking to it's abnormal inner oven temp and is not moving. I'll let it cook a little longer then may have to do some invasive diagnostics. I keep an odd assortment of whatever-I-can-find oscillators around the lab for use as external time base clocks for frequency counters that I use to look at frequency offsets in stabilized light sources by heterodyning their outputs against a calibrated optical source to generate more easily measured RF products in the microwave range. I'm hoping this little guy will start to show its stuff soon. Greg ___ 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] OT - but of interest?
Jim Lux wrote: It's been challenging to find out information like Center of Mass position, where the other GPS receivers are, etc. (complicated in part because half of station is measured in inches/feet, and the other half in meters) This reminds me of a story I heard about while building the packet module power supply for the Russian module of the ISS. Apparently when the Russians copied the type-N connector blueprints from the west, they used an incorrect english to metric conversion factor, such that Russian-made type-N connectors will not mate correctly with US type-N connectors (unless you use force). I have not personally verified this story, just passing it along for your consideration. On the subject of cell phones in space, since the cost of placing anything in orbit is approximately equal to the value of an equivalent mass of pure gold, efforts to do extreme cost reduction at the expense of reliability seem misplaced. A $100K Cubesat costs about the same amount to place into orbit. Getting the cost of the satellite down to a thousand dollars makes little sense when it still costs $100K to put that satellite into orbit. If the satellite dies early from radiation exposure you wasted the money that you spent to launch it. And it is unnecessary to adapt terrestrial consumer products for satellites when there are other good options to obtain components engineered for the space environment at reasonable cost. AMSAT has decades of experience in this area. Cell phones are consumer devices, exquisitely engineered for mass production with reasonably high reliability (when used on Earth as intended) at minimum per unit cost. Consumer electronics is a highly specialized area of engineering, but so is space flight hardware. Using consumer electronic devices in a space flight environment is a misapplication of engineering principles and is destined to be a technological dead-end. Dan Schultz N8FGV ___ 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] HP5065B !!!
Has anyone considered a laser pumped variant like: http://tf.nist.gov/general/pdf/1009.pdf Apart from the ECDL laser (can be assembled using readily availalble parts) it looks fairly straightforward. Bruce Tom Van Baak wrote: Very nice bit of RD work on Corby's part. Mine is certainly working well after the modification, but I'm just blown away at the performance seen with Tom's unit. Hi John, Yes, apparently some 5065A respond better than others to Corby's clever mod. It's clear why there is improvement; it's an interesting challenge/mystery to understand why some get more improvement than others. I double checked its performance with both a TSC 5110A/5120A and your TimePod to be sure it wasn't me. In general, some HP 5065A are better than others. OTOH, this is somewhat true for any frequency standard: from pendulum to quartz to rubidium to cesium to hydrogen. It drives time nuts crazy (and turns some of us into eBay gold diggers) but this has been the case from the first hand-made quartz oscillators in the 1920's to, well, the hand-made GPS Rubidium's, or the hand-made cesium fountains of today. Every clock is slightly different. You can be practical and live with it, or a fanatic and keep searching for a slightly better one or finding out why and putting effort into tweaking parameters, swapping components, or boards, etc. I know Corby has done an amazing job over the years with vintage cesium and rubidium standards. I hope to have him upgrade some of my 5065A too. Just to clarify -- the excellent plot that Corby posted was a modified 5065A that I tested *for* him, not one that I actually own. So it's not Tom's unit, but one that Tom enjoyed testing. Note the baseline was a PHM vs. AHM, just to show the noise floor of the measurement system(s) and reference(s). /tvb Another plot of the Super mod that's worth mentioning: http://www.ke5fx.com/5065A_vs_maser_mask.png Below 1000 seconds it has no trouble passing the spec limits for a passive H-maser! For contrast, teeypical LPRO-101 performance is shown in green, and the red trace is from the second-best commercial Rb standard I've seen (Symmetricom XPRO). -- john, KE5FX Miles Design LLC -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts- boun...@febo.com] On Behalf Of cdel...@juno.com Sent: Friday, April 26, 2013 8:24 AM To: time-nuts@febo.com Subject: [time-nuts] HP5065B !!! OK, that was just to get your attention! What do you call a modified HP 5065A that can give you an Allan Deviation of 4X10-13 @ 1 Second and 6X10-14 @ 100 Second? I call it the SUPER HP 5065A. Any of these links will get you to the document describing it. Have a look and see what it's all about! Enjoy, Corby http://leapsecond.com/corby/Super-5065A-Project.pdf or http://leapsecond.com/corby/superproj10.docx or http://www.febo.com/pages/HP5065A_SUPER for ___ 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.
