[time-nuts] Distribution Amps
List, There has been a large exchangeof ideas for various home-brew or other video box alternatives which all wouldseem to work OK. For me it was simpler to buy asurplus HP 5087A for best offer which turned out to be $300 delivered. Besides having 12 outputs, youhave a choice of 3 inputs. It alsoaccepts IIRC 1, 5, and 10 MHz input signals. I probably will never use all ofits capabilities but for my needs it was the best choice. Also if your pacemaker isn’t intop-notch order, you may not want to look at the prices of its newerreplacement. Regards, Perrier ___ 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] 5 to 10 MHz doublers
List, There has been a lot ofinformation on the list for 5 MHz frequency doublers. As it is easier for me to buythan make, would using something like a Mini-Circuits surplus DBM’s be anacceptable way to go? Regards, Perrier ___ 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] 10811 Alternatives
I would personally consider those MV89s from Chinese sources as being extra suspect - a few years back, one of the Chinese surplus vendors had a big box of them (some removed from PCBs, and others apparently new) that were identified to me as containing bad ceramic caps and suffering from various problems ranging from poor phase noise performance to being completely inoperative. The guy who had them (who I know quite well) volunteered this information and said that as far as he was concerned they could only be sold as scrap - but it's possible they have ended up in the hands of dealers that are not so scrupulous. On Mon, Apr 13, 2015 at 8:46 AM, Bob Camp kb...@n1k.org wrote: Hi I don’t think there’s anything at all wrong with the MV-89A as an OCXO. In fact, I believe that properly handled they are a good part. The gotcha is the abuse they get in the “recycling” process. I’m willing to bet that any OCXO that sees the same sort of process will come out with issues. Bottom line - Don’t attack an OCXO with a torch, drop it down a flight of stairs, leave it out in the rain for a few years, and then really abuse it after that. They need to be treated with some care …. For what ever reason, parts like IC’s seem to be more tolerant of the scrap out process than OCXO’s. Rb’s seen to show up *with* PCB’s still attached, so they didn’t get the torch process. Because of all that, there’s not much way to pick a “good” OCXO model. The thing you need to find are parts that you are sure did not take a beating while being pulled off of boards. With zero view into that end of the sourcing process …. not much way to pick and choose. About the only thing to do is to buy parts that never went on to pc boards. That’s no guarantee, but it ups the odds a bit. You may be buying test rejects. They could still have been dropped down a flight of stairs. They might be counterfeit parts. Considering that you are buying a $250 to $400 OCXO for $20, there *will* always be some risk …. Bob On Apr 12, 2015, at 6:02 PM, Perry Sandeen via time-nuts time-nuts@febo.com wrote: List, It appears from Bob Camp’sexperience (and others) that the Chicoms Morion oscillators are to be avoided. My question is: Could Bob Camp,Rick K. and other gurus with experience come up with a list of the Ebay 10 MHzsurplus oscillators that would be worth buying as well as what would be a fairprice? Also some good vendor names would be nice as well. I realize that surplus listvaries quite a bit and it still a bit of a crap shoot, but perhaps the odds arebetter from certain venders, makes, and models. Regards, Perrier ___ 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] Ultra High Stability Time Base Options for 53132A
On 4/12/2015 6:30 PM, Attila Kinali wrote: It might be that I'm already too sleepy, but I don't see why a faster comparator would add more jitter. Actually, my intuition (which is clearly wrong) would say the contrary. So, which effect does increase the jitter with comparator speed? The faster the comparator, the greater its analog bandwidth. Thus there is more total noise to cause jitter. The DC to daylight comparator is the opposite of the John Dick (JPL) paper on zero crossing detectors in PTTI around 1990. John teaches that you use the MINIMUM bandwidth amplifier to square up a sine wave. BTW: If anyone here has any good text to read on oscillator design, please let me know. I'm collecting those :-) Attila Kinali Start by reading everything by: Marv Frerking Mike Driscoll John Vig Oh, and I wrote a few papers on oscillators myself :-) Rick ___ 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] Ultra High Stability Time Base Options for 53132A
On Sun, 12 Apr 2015 16:48:37 -0700 Richard (Rick) Karlquist rich...@karlquist.com wrote: Of course you're right, any comparator will add jitter to a 10811. The faster they are, the more jitter they add. It might be that I'm already too sleepy, but I don't see why a faster comparator would add more jitter. Actually, my intuition (which is clearly wrong) would say the contrary. So, which effect does increase the jitter with comparator speed? I noticed that the standard 10 MHz oscillator is built with an ECL line receiver. Another example of Menken's saying. This is a TERRIBLE oscillator design, but one that would appeal to the non-initiated. Well, for that you'd need to understand what an oscillator actually is and how it works. The knowledge of that is hardly taught anymore. And those people who know how to properly design an oscillator are either nearing retirement or are already retired. BTW: If anyone here has any good text to read on oscillator design, please let me know. I'm collecting those :-) Attila Kinali -- _av500_ phd is easy _av500_ getting dsl is hard ___ 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] Ultra High Stability Time Base Options for 53132A
On 4/12/2015 2:22 PM, Magnus Danielson wrote: Hi, The buffer transistors has not AC-bypass of the emitter resistance, so that the DC current becomes large and thus contributes flicker noise. The comparator at the bottom isn't doing a beutifull work of squaring things up without contributing noise, considering the sine output of the 10811. Was that it, Rick? Cheers, Magnus The resolution of page 13 is poor, and it seems to be a bitmap instead of a vector file. The fuzzy thing in the lower right corner looks like it might be a comparator. I think this was the smoking gun. There was a saying by H.L. Menken to the effect that for every complex problem, there is a simple, obvious, invalid solution. Squaring up a 10811 with a comparator is a perfect example of this principle. Non-time-nuts always seem to gravitate to this design. Of course you're right, any comparator will add jitter to a 10811. The faster they are, the more jitter they add. I noticed that the standard 10 MHz oscillator is built with an ECL line receiver. Another example of Menken's saying. This is a TERRIBLE oscillator design, but one that would appeal to the non-initiated. I built one of these oscillators in 1976 at the suggestion of my boss. After seeing how bad it was, I quietly designed it out and never used it again. Rick Karlquist N6RK ___ 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] 10811 Alternatives
Hi I don’t think there’s anything at all wrong with the MV-89A as an OCXO. In fact, I believe that properly handled they are a good part. The gotcha is the abuse they get in the “recycling” process. I’m willing to bet that any OCXO that sees the same sort of process will come out with issues. Bottom line - Don’t attack an OCXO with a torch, drop it down a flight of stairs, leave it out in the rain for a few years, and then really abuse it after that. They need to be treated with some care …. For what ever reason, parts like IC’s seem to be more tolerant of the scrap out process than OCXO’s. Rb’s seen to show up *with* PCB’s still attached, so they didn’t get the torch process. Because of all that, there’s not much way to pick a “good” OCXO model. The thing you need to find are parts that you are sure did not take a beating while being pulled off of boards. With zero view into that end of the sourcing process …. not much way to pick and choose. About the only thing to do is to buy parts that never went on to pc boards. That’s no guarantee, but it ups the odds a bit. You may be buying test rejects. They could still have been dropped down a flight of stairs. They might be counterfeit parts. Considering that you are buying a $250 to $400 OCXO for $20, there *will* always be some risk …. Bob On Apr 12, 2015, at 6:02 PM, Perry Sandeen via time-nuts time-nuts@febo.com wrote: List, It appears from Bob Camp’sexperience (and others) that the Chicoms Morion oscillators are to be avoided. My question is: Could Bob Camp,Rick K. and other gurus with experience come up with a list of the Ebay 10 MHzsurplus oscillators that would be worth buying as well as what would be a fairprice? Also some good vendor names would be nice as well. I realize that surplus listvaries quite a bit and it still a bit of a crap shoot, but perhaps the odds arebetter from certain venders, makes, and models. Regards, Perrier ___ 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] 5 to 10 MHz doublers
The 5071A doublers I designed use MCL ASK-1 mixers. The LO and RF ports are connected in series. This arrangement is self limiting. So you drive them fairly hard and the output is level. The IF port needs to see a DC short circuit of course. This was essential in the 5071A since there were 5 doublers in cascade. The input impedance is about 30 ohms and you need a fair amount of drive, like 30 mA peak to peak. I tested and rejected other approaches like putting the ports in parallel or driving them with a quadrature hybrid. The series connection just worked better. It's going on 25 years, but this is what I remember. The filtering is another non-trivial story. Buying DBM's doesn't make that job any easier. Rick Karlquist N6RK On 4/12/2015 3:10 PM, Perry Sandeen via time-nuts wrote: List, There has been a lot ofinformation on the list for 5 MHz frequency doublers. As it is easier for me to buythan make, would using something like a Mini-Circuits surplus DBM’s be anacceptable way to go? Regards, Perrier ___ 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] Ultra High Stability Time Base Options for 53132A
Hi The fuzzy blob would appear to be an LM361 “high speed (20 ns)” comparator. Surely it must have a jitter below a couple of nanoseconds :) Even that is only a guess since jitter is never mentioned in the spec sheet I dug up: http://www.ti.com/lit/ds/symlink/lm361.pdf Bob On Apr 12, 2015, at 7:48 PM, Richard (Rick) Karlquist rich...@karlquist.com wrote: On 4/12/2015 2:22 PM, Magnus Danielson wrote: Hi, The buffer transistors has not AC-bypass of the emitter resistance, so that the DC current becomes large and thus contributes flicker noise. The comparator at the bottom isn't doing a beutifull work of squaring things up without contributing noise, considering the sine output of the 10811. Was that it, Rick? Cheers, Magnus The resolution of page 13 is poor, and it seems to be a bitmap instead of a vector file. The fuzzy thing in the lower right corner looks like it might be a comparator. I think this was the smoking gun. There was a saying by H.L. Menken to the effect that for every complex problem, there is a simple, obvious, invalid solution. Squaring up a 10811 with a comparator is a perfect example of this principle. Non-time-nuts always seem to gravitate to this design. Of course you're right, any comparator will add jitter to a 10811. The faster they are, the more jitter they add. I noticed that the standard 10 MHz oscillator is built with an ECL line receiver. Another example of Menken's saying. This is a TERRIBLE oscillator design, but one that would appeal to the non-initiated. I built one of these oscillators in 1976 at the suggestion of my boss. After seeing how bad it was, I quietly designed it out and never used it again. Rick Karlquist N6RK ___ 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] Distribution Amps
On 4/12/2015 3:04 PM, Perry Sandeen via time-nuts wrote: List, For me it was simpler to buy asurplus HP 5087A for best offer which turned out to be $300 delivered. The 5087 series is ancient technology that has mediocre performance. I remember looking at the circuit designs in the series in case I wanted to leverage them for the 5071A. There was nothing that would be of interest for the 5071A. If the 5087 meets your needs, then fine. But many time nuts need something better. Rick Karlquist N6RK ___ 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] [Bulk] Re: Ultra High Stability Time Base Options for 53132A
Tom, Unfortunately, it would appear that there is an 'older' version of circuits (?CLIP as well). My Osc Support Board for the Opt 010 version of the 10811 is a 53132-60011 which is populated with a number of components that are not present on the 53132-60016 board, the board that seems to be used with my (S/N 3736Ax) 53132-60014 Main Board. The 53132-60011 Osc Support Board connects to a 531332-60010 Time Base Output Select Board. On my unit, there are holes in the side panel at the rear of the right side (as viewed from the front) that would appear to mate with the 53132-60010 board and there are unpopulated connections that would appear to mate with the connections from the 531332-60010 board. I can find no mention of the 53132-60010 board in any of the manuals I have. It has a DPDT relay on the board, a couple of voltage regulators (317M and 78M05) and a MC1413D chip, a High Voltage, High Current Darlington Transistor Array. There is a connection from the 53132-60011 board and two connections that appear to connect to the Main Board. I have pictures of the boards if anyone is interested. I wonder if this is what Rick is referring to and that the 53132A might have been modified later to use the 53132-60016 board and an 'updated' Main Board. And, perhaps, better performance? It would be nice if anyone had an older version of the CLIP (or 53132A) that might explain this. Thanks. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Tom Van Baak Sent: Sunday, April 12, 2015 11:50 AM To: Discussion of precise time and frequency measurement Subject: [Bulk] Re: [time-nuts] Ultra High Stability Time Base Options for 53132A Hi Rick, It is our good fortune that some years ago Agilent/Keysight released the schematics to the 53131A/53132A counters: http://literature.cdn.keysight.com/litweb/pdf/5989-6308EN.pdf Have a look and see if you can recreate the details that you remembered. I too have noticed on some tests that the counter seems to ruin the benefit of a good external timebase. This is even more true of the newer 53230-series counters. Maybe get rid of the PLL and use a int/ext toggle switch like the 70's. So it would be nice if you or other circuit experts on the list could point out the flaw(s) -- I'm sure a couple of time nuts would even be willing to mod their 53132A boards based on some suggestions on what to try. Thanks, /tvb ___ 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] 10811 Alternatives
List, It appears from Bob Camp’sexperience (and others) that the Chicoms Morion oscillators are to be avoided. My question is: Could Bob Camp,Rick K. and other gurus with experience come up with a list of the Ebay 10 MHzsurplus oscillators that would be worth buying as well as what would be a fairprice? Also some good vendor names would be nice as well. I realize that surplus listvaries quite a bit and it still a bit of a crap shoot, but perhaps the odds arebetter from certain venders, makes, and models. Regards, Perrier ___ 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] Ultra High Stability Time Base Options for 53132A
Hi, The buffer transistors has not AC-bypass of the emitter resistance, so that the DC current becomes large and thus contributes flicker noise. The comparator at the bottom isn't doing a beutifull work of squaring things up without contributing noise, considering the sine output of the 10811. Was that it, Rick? Cheers, Magnus On 04/12/2015 06:50 PM, Tom Van Baak wrote: Hi Rick, It is our good fortune that some years ago Agilent/Keysight released the schematics to the 53131A/53132A counters: http://literature.cdn.keysight.com/litweb/pdf/5989-6308EN.pdf Have a look and see if you can recreate the details that you remembered. I too have noticed on some tests that the counter seems to ruin the benefit of a good external timebase. This is even more true of the newer 53230-series counters. Maybe get rid of the PLL and use a int/ext toggle switch like the 70's. So it would be nice if you or other circuit experts on the list could point out the flaw(s) -- I'm sure a couple of time nuts would even be willing to mod their 53132A boards based on some suggestions on what to try. Thanks, /tvb - Original Message - From: Richard (Rick) Karlquist rich...@karlquist.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, April 12, 2015 8:30 AM Subject: Re: [time-nuts] Ultra High Stability Time Base Options for 53132A On 4/12/2015 1:03 AM, Adrian Godwin wrote: What caused that degradation ? I'm interested in dos/don'ts for best use of a 10811. I don't remember the details much after 25 years, but basically they have a distribution amplifier that allows for internal or external 10 MHz and what I remember is that I looked at the schematic and concluded that no one with a background in precision time and frequency would design it that way. And it turned out that the person who designed it did not have any such background. I vaguely require some measurement that had disappointing results that caused me to want to look at the schematic of it in the first place. Rick ___ 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] Ultra High Stability Time Base Options for 53132A
Hallo Hans, I too have Gerry Sweeny's OCXO running im my 53131A. Would be really great to see the results of the tests mentioned by you. TIA Ulli ___ 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] [Bulk] Re: Ultra High Stability Time Base Options for 53132A
Bob, Thanks for your thoughts. It is hard to tell from the pictures that accompany the items but it appears some use the 'Vref' pin to obtain the control voltage and some do not. If that indeed is the case, I wonder if using the Vref pin would offer a greater likelihood of better performance. Also, how would you go about testing these Time Bases or 53132A? Installing them in the 53132A, leave them on for 24 hours, do the 'CALTIMBAS' routine, then use the 53132A to measure your 'best' source? If so, which source would you use? I have GPSDO (TBolt, Z3816A, Z3805A, Lucent Z3810A, Lucent RFTGm-II-XO and Rb), Rb (5065A, LPRO, and others) or CS (5061A). Also, how would you set up the 53132A and collect the data? My question is how can I get the most stable and accurate 'stand-alone' counter, not having to connect an external reference? Thanks for your help. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Saturday, April 11, 2015 5:04 PM To: Discussion of precise time and frequency measurement Subject: [Bulk] Re: [time-nuts] Ultra High Stability Time Base Options for 53132A Hi All of the MV-89’s that I have seen are very much a crap shoot in terms of what you get. Out of a dozen or so I’ve bought from various sources, none has met the original specs on the unit. There have been a wide range of issues. Doing a full test on one involves a lot of work. The problems with some of them are major the problems with others are fairly hard to spot. I do not believe that’s a reflection on the original design of the part. I’d bet that nearly 100% of them meet spec when new. I think it’s purely due to the amount of violence done to them when they are pulled from boards during the savage process. Bob On Apr 11, 2015, at 8:01 AM, J. L. Trantham jlt...@att.net wrote: Has anyone done any testing/comparison of the three aftermarket UHS Time Base Options for the 53132A that are on theBay? One is from Poland: 111643536543 Two are from China: 181698758773 and 331420737911 All use the Morion MV89A and all appear to be 'plug and play' with the automated time base calibration process of the 53132A. I recently added the 3 GHz Prescaler from the seller in Poland (111631156891) and was very satisfied. No connection other than a satisfied customer. I also recently added the HP Opt 010, one of the 10811 based time bases, and was very satisfied as well. Just wondering if there is something better. Thanks in advance for any thoughts. Joe ___ 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] Ultra High Stability Time Base Options for 53132A
What caused that degradation ? I'm interested in dos/don'ts for best use of a 10811. On Sat, Apr 11, 2015 at 11:32 PM, Richard (Rick) Karlquist rich...@karlquist.com wrote: On 4/11/2015 5:01 AM, J. L. Trantham wrote: Unless the design has been changed, the 10811 option for the 53132 has poor short term stability and degrades the performance of the 10811 by something like an order of magnitude. I complained about this when the counter first came out 25 years ago but no one would listen. At the time I had recently transferred out of counter RD to work on the 5071A. Rick Karlquist N6RK ___ 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] Counter averaging errors near clock harmonics
Charles. On 04/10/2015 09:27 PM, Charles Steinmetz wrote: The subject of errors in averaging counters at input frequencies near the clock frequency and its subharmonics and harmonics comes up on the list from time to time. There is a nice discussion of the phenomenon, and how it was addressed in the design of the HP 5345A counter, in the June, 1974 issue of the Hewlett-Packard Journal: David C. Chu, Time Interval Averaging: Theory, Problems, and Solutions, HP Journal v25 n10, June 1974 www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1974-06.pdf Good point. This technique is also used in the HP5328A, but only for TI averaging, not for frequency measurement. 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] [Bulk] Re: Ultra High Stability Time Base Options for 53132A
Hi On Apr 12, 2015, at 8:03 AM, J. L. Trantham jlt...@att.net wrote: Bob, Thanks for your thoughts. It is hard to tell from the pictures that accompany the items but it appears some use the 'Vref' pin to obtain the control voltage and some do not. If that indeed is the case, I wonder if using the Vref pin would offer a greater likelihood of better performance. A lot depends on if the example you get *has* voltage on the Vref output or not. You can come up with a stable reference source. without using it. Also, how would you go about testing these Time Bases or 53132A? Simple approach: 1) Apply power, see if the controller cuts back, toss out about 1 in 5 because they don’t. Simple check with a DVM. 2) Check output power with a power meter. X mark the ones that have 2 dbm out into a pile. That’s about 3 out of 5. 3) Check the output for spurs (not sub harmonics, but true spurs) on a spectrum analyzer. X mark the ones that have issues. That’s maybe 1 in 12. 4) Toss them on a TimePod and compare them to something good. X mark anything with ADEV 5x10^-12 at 1 to 10 seconds. That’s about 3 out of 5. 5) Check the same data for phase noise. X mark anything with major humps in it. That’s maybe 1 in 5 5) Toss them in a Delta chamber and do a temp run. Look at the data. X mark anything that’s over 1x10^-9 p-p. That’s about 3 out of 5 6) Apply voltage to the EFC pin and X mark any that don’t at least trim +/- 5x10^-8. That’s about 2 out of 5. Now try and sort through the pile for any that either were not tossed out at step one or made it through with no X marks. Multiple X marks are not terribly surprising because there may be a common failure that impacts multiple specs. So far I have not seen any without X marks on them. It is interesting to note that the “low power out” X marks do not correlate to a very great extent with the other failures. There’s a fairly well known capacitor failure at the output stage that impacts power without messing up things like ADEV or temperature stability. Again, when new or properly installed there would be no toss outs or X marks on any oscillators in a 10 to 20 piece sample. You would have to get a much larger test group to have any chance of finding a problem unit (if you could at all). The fact that 100% of the parts had some sort of issue says to me that the handling of the parts was not at all good. Installing them in the 53132A, leave them on for 24 hours, do the 'CALTIMBAS' routine, then use the 53132A to measure your 'best' source? If so, which source would you use? I have GPSDO (TBolt, Z3816A, Z3805A, Lucent Z3810A, Lucent RFTGm-II-XO and Rb), Rb (5065A, LPRO, and others) or CS (5061A). Also, how would you set up the 53132A and collect the data? The gotcha is that the 53132 is not accurate enough to take some of the key data above all by it’s self. My question is how can I get the most stable and accurate 'stand-alone' counter, not having to connect an external reference? If you are going to run a counter stand alone, *and* turn it on and off, old cell site OCXO’s may not be your best bet. Their warmup characteristics will probably get in the way. Those OCXO’s were designed to be turned on once and run for years and years. A run in of three days was not at all uncommon. Bob Thanks for your help. Joe -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of Bob Camp Sent: Saturday, April 11, 2015 5:04 PM To: Discussion of precise time and frequency measurement Subject: [Bulk] Re: [time-nuts] Ultra High Stability Time Base Options for 53132A Hi All of the MV-89’s that I have seen are very much a crap shoot in terms of what you get. Out of a dozen or so I’ve bought from various sources, none has met the original specs on the unit. There have been a wide range of issues. Doing a full test on one involves a lot of work. The problems with some of them are major the problems with others are fairly hard to spot. I do not believe that’s a reflection on the original design of the part. I’d bet that nearly 100% of them meet spec when new. I think it’s purely due to the amount of violence done to them when they are pulled from boards during the savage process. Bob On Apr 11, 2015, at 8:01 AM, J. L. Trantham jlt...@att.net wrote: Has anyone done any testing/comparison of the three aftermarket UHS Time Base Options for the 53132A that are on theBay? One is from Poland: 111643536543 Two are from China: 181698758773 and 331420737911 All use the Morion MV89A and all appear to be 'plug and play' with the automated time base calibration process of the 53132A. I recently added the 3 GHz Prescaler from the seller in Poland (111631156891) and was very satisfied. No connection other than a satisfied customer. I also recently added the HP Opt 010, one of the 10811 based time bases, and was
Re: [time-nuts] Ultra High Stability Time Base Options for 53132A
Hi The savage was a typo, but I suspect that in this one case the typo may have been pretty accurate. Based on the pictures I’ve seen of the people salvaging the boards, it’s not a very precise process. Bob On Apr 12, 2015, at 7:33 AM, James via time-nuts time-nuts@febo.com wrote: Was the savage deliberate or did you mean salvage - they are probably both accurate.:) James -Original Message- From: Bob Camp kb...@n1k.org To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sun, 12 Apr 2015 0:17 Subject: Re: [time-nuts] Ultra High Stability Time Base Options for 53132A Hi All of the MV-89’s that I have seen are very much a crap shoot in terms of what you get. Out of a dozen or so I’ve bought from various sources, none has met the original specs on the unit. There have been a wide range of issues. Doing a full test on one involves a lot of work. The problems with some of them are major the problems with others are fairly hard to spot. I do not believe that’s a reflection on the original design of the part. I’d bet that nearly 100% of them meet spec when new. I think it’s purely due to the amount of violence done to them when they are pulled from boards during the savage process. Bob On Apr 11, 2015, at 8:01 AM, J. L. Trantham jlt...@att.net wrote: Has anyone done any testing/comparison of the three aftermarket UHS Time Base Options for the 53132A that are on theBay? One is from Poland: 111643536543 Two are from China: 181698758773 and 331420737911 All use the Morion MV89A and all appear to be 'plug and play' with the automated time base calibration process of the 53132A. I recently added the 3 GHz Prescaler from the seller in Poland (111631156891) and was very satisfied. No connection other than a satisfied customer. I also recently added the HP Opt 010, one of the 10811 based time bases, and was very satisfied as well. Just wondering if there is something better. Thanks in advance for any thoughts. Joe ___ 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] Ultra High Stability Time Base Options for 53132A
Hi Rick, It is our good fortune that some years ago Agilent/Keysight released the schematics to the 53131A/53132A counters: http://literature.cdn.keysight.com/litweb/pdf/5989-6308EN.pdf Have a look and see if you can recreate the details that you remembered. I too have noticed on some tests that the counter seems to ruin the benefit of a good external timebase. This is even more true of the newer 53230-series counters. Maybe get rid of the PLL and use a int/ext toggle switch like the 70's. So it would be nice if you or other circuit experts on the list could point out the flaw(s) -- I'm sure a couple of time nuts would even be willing to mod their 53132A boards based on some suggestions on what to try. Thanks, /tvb - Original Message - From: Richard (Rick) Karlquist rich...@karlquist.com To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, April 12, 2015 8:30 AM Subject: Re: [time-nuts] Ultra High Stability Time Base Options for 53132A On 4/12/2015 1:03 AM, Adrian Godwin wrote: What caused that degradation ? I'm interested in dos/don'ts for best use of a 10811. I don't remember the details much after 25 years, but basically they have a distribution amplifier that allows for internal or external 10 MHz and what I remember is that I looked at the schematic and concluded that no one with a background in precision time and frequency would design it that way. And it turned out that the person who designed it did not have any such background. I vaguely require some measurement that had disappointing results that caused me to want to look at the schematic of it in the first place. Rick ___ 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] 53132 Option 012 Aging
Hi nuts - I ran into this information on the Keysight site. The aging rate of a Keysight Option 012 ultra-high-stability oven in the first 90 days is: 1E-10 *30 days + 3E-9 * 2 months = 9E-9 In the first year, the aging rate is: 1E-10 *30 days + 3E-9 * 11 months = 3.6E-8 The second year (without adjustments) the aging rate is: 1E-10 *30 days + 3E-9 * 11 months + 2E-8*1 year = 5.6E-8 Above is from: Tips for making more accurate measurements with a frequency counter http://www.keysight.com/main/editorial.jspx?cc=US http://www.keysight.com/main/editorial.jspx?cc=USlc=engckey=505277nid=-3 3788.536880944.00id=505277 lc=engckey=505277nid=-33788.536880944.00id=505277 It makes a case for using a GPSDO or other external reference or frequent re-calibrations of the -012 oscillator. Regards, John --- This email has been checked for viruses by Avast antivirus software. http://www.avast.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] Ultra High Stability Time Base Options for 53132A
On 4/12/2015 1:03 AM, Adrian Godwin wrote: What caused that degradation ? I'm interested in dos/don'ts for best use of a 10811. I don't remember the details much after 25 years, but basically they have a distribution amplifier that allows for internal or external 10 MHz and what I remember is that I looked at the schematic and concluded that no one with a background in precision time and frequency would design it that way. And it turned out that the person who designed it did not have any such background. I vaguely require some measurement that had disappointing results that caused me to want to look at the schematic of it in the first place. Rick ___ 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] 53132 Option 012 Aging
Hi The biggest issue I have seen with internal OCXO’s on counters is the actual use case: Case A I have the counter mounted in a rack / on a bench and it’s always on power. Case B I have the counter on the shelf and pull it down and plug it in when I need to use it, once I’m done I unplug it and put it back on the shelf. Case C other. From what I’ve seen, roughly 99% of the use falls into either case A or case B. In case A above, adding a GPSDO is not a big deal. It benefits all the gear in the rack, not just the counter. It may (or may not) pull less power than the counter on idle. If the GPSDO fries from long use, it’s less expensive to replace than a fancy counter. Case B is where the problem is. In case B above, the normal “warm it up for 5 or 10 minutes” approach likely leads to an error on the order of 1x10^-8 or more. It’s better than a TCXO, but not by as much as it should be.It’s also enough to significantly degrade the accuracy of the counter. Worse, the drift over the next hour or so will drive you a bit nuts if you *need* accuracy in what you are doing. To get good stability out of an OCXO and not have it on power all the time, you need to be in case C. More or less: 1) Decide I will use the counter tomorrow. 2) Pull it down off the shelf and let it warm up overnight. 3) Do my testing and unplug it when done. Yes indeed somewhere there is somebody that organized. If so, I have yet to meet them :) Is that the whole story - of course not. It *is* worth considering when looking at an internal OCXO conversion that likely shortens the lifespan of the counter (more heat / power supply load / fan time …). Some alternatives: 1) Cheap rubidium in a box - no “couple of days” warmup / retrace stuff to deal with 2) OCXO + batteries in a box - just the OCXO runs, the counter is turned off 3) Lightweight GPSDO - locks up about as fast as the Rb, can be quite accurate. None of the alternatives are massively expensive. Options 2 and 3 can be quite a bit smaller than the counter. Option 1 might be about the size of a 53131. Bob On Apr 12, 2015, at 12:39 PM, John Allen j...@pcsupportsolutions.com wrote: Hi nuts - I ran into this information on the Keysight site. The aging rate of a Keysight Option 012 ultra-high-stability oven in the first 90 days is: 1E-10 *30 days + 3E-9 * 2 months = 9E-9 In the first year, the aging rate is: 1E-10 *30 days + 3E-9 * 11 months = 3.6E-8 The second year (without adjustments) the aging rate is: 1E-10 *30 days + 3E-9 * 11 months + 2E-8*1 year = 5.6E-8 Above is from: Tips for making more accurate measurements with a frequency counter http://www.keysight.com/main/editorial.jspx?cc=US http://www.keysight.com/main/editorial.jspx?cc=USlc=engckey=505277nid=-3 3788.536880944.00id=505277 lc=engckey=505277nid=-33788.536880944.00id=505277 It makes a case for using a GPSDO or other external reference or frequent re-calibrations of the -012 oscillator. Regards, John --- This email has been checked for viruses by Avast antivirus software. http://www.avast.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 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] Ultra High Stability Time Base Options for 53132A
i have a 53132A and the the time base from the polish seller as well as a time base from gerry sweeny (UK) who uses a trimble 34310-T instead of the morion ocxo. both are plug and play and can be easily calibrated. i have no data, but if i remember correctly, the presence of a high stability time base degrades the measured short term stability of any DUT, if i use an external reference such as a gpsdo. if you are interested i could do the following: measure TI between a trimble thunderbolt and a trimble 73090 docxo that has been running for several weeks 1. without external reference: no high stability time base, morion time base, trimble time base 2. the same, but with an external reference (TB). that will take some time. but i am intersted in this myself, so i could give it a try. hans ___ 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] KS-24361 Power Module Repair
This seems a bit toasty and is equivalent to 284F. Maybe meant 140F not C? An oven set to 140C is your friend when doing jobs like this. FWIW, the GE Progress Line two-way radios oscillator crystal holders had an octal base, held two crystals, and the heating element could be used on 6 volts or 12 volts depending on which way the holder was plugged in. I have no idea of how well they held the temperature. Always planned to use one with an external proportional controller but never got around to it. Al, k9si ___ 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.
