No question about that. The morion does run a little warmer than the old unit apparently did. Fan is temp-controlled, so I think OK. will monitor box temp with a digital :-) thermometer, very poor resolution, but probably ok. When I get the last obs done. will do a little blurb to the group. Don
Bob Camp > Hi > > That sounds fine. Without knowing just what they did or didn’t do, it’s always > worth being a bit careful. > > Bob > >> On Nov 23, 2014, at 6:40 PM, Don Latham <[email protected]> wrote: >> >> Running very nearly continuously for about 4 days now. The self-measured >> jitter is mean 0 and sdev of 8 ps. I don't think there is a problem with the >> Morion. I'm using my newly acquired cs source and a couple of z3801's for >> checking. 1 bit on the SR's frequency calibration dac seems to be about 4-5 >> parts in 10^-10 if I'm reading things right. Next test is a z3801 driving >> the >> external freq port on the sr to see if the frequency change direction of the >> morion is OK. >> The scope display output from the SR620 is great! >> Lots to learn. Also have one of Said's units coming. Gone nuts for time, >> won't >> do anything much new, but it's new to me. All this to drive moonbounce... >> Don >> >> >> Bob Camp >>> Hi >>> >>> If all the “good stuff” runs on the 90 MHz, the 5 MHz issue may not be >>> important at all. It’s just something to watch for. If you start seeing >>> data >>> in two groups, each one 20 ps wide and separated by maybe 200 ps, you are >>> seeing a problem from the 5 MHz. >>> >>> Running the box for a while before doing a full detailed cal is a very good >>> idea. It’s a bit warm inside and some of the stuff is temperature >>> sensitive. >>> You want it to reach equilibrium. >>> >>> Bob >>> >>>> On Nov 23, 2014, at 1:06 AM, Don Latham <[email protected]> wrote: >>>> >>>> Ah. Got it finally! Doh. Just finished trying out the Morion this >>>> afternoon. >>>> Electrically works very well. Used a 7812 to drop the +15 volts from the >>>> option 1 ocxo, there is enough power headroom to bring the Morion up from >>>> cold >>>> and run it comfortably. As you said, the control voltage for the original >>>> is >>>> indeed 5 v, and can be set by the internal d/a. The output of the >>>> oscillator >>>> passes through an emitter follower voltage adjuster and through a low-q >>>> filter >>>> to three stages of ECL buffer and then out to the 10 MHz system bus clock. >>>> Another path proceeds to a relay-switched divide by 2 to the phase >>>> detector >>>> so >>>> an external 5/10 MHz source can lock the internal oscillator. >>>> The external 5/10 MHz source proceeds to the phase detector thru an >>>> identical >>>> buffer chain without the switched divider. The remainder of the clock >>>> circuits is a multiplier to 90 MHz. >>>> >>>> I'll run the autocal tomorrow and then get some jitter stats if possible. >>>> This >>>> is an early specimen, s/n about 700 or so. I can imagine seldom used, and >>>> sitting on standby for 20 years or so, pushing the ocxo out of tolerance. >>>> >>>> The saga continues; I may have to look for a 10 MHz replacement on epay, >>>> there >>>> isn't room to put in an Hp, unfortunately. >>>> Don >>>> >>>> >>>> >>>> >>>> Bob Camp >>>>> Hi >>>>> >>>>> At least the Morion’s I have seen have 5 MHz crystals in them rather than >>>>> 10 >>>>> MHz. They have a 10 MHz output due to an internal doubler. Since the >>>>> circuit >>>>> is not perfect, there is cycle to cycle variation in the 10 MHz. It’s way >>>>> more >>>>> jitter (measured in picoseconds) than the oscillator has due to phase >>>>> noise. >>>>> My concern is that a counter might be bothered by this is some subtle >>>>> way. >>>>> >>>>> Bob >>>>> >>>>>> On Nov 22, 2014, at 3:55 PM, Don Latham <[email protected]> wrote: >>>>>> >>>>>> Hi Bob: no. cobble, not double :-) A little research has me thinking I >>>>>> can >>>>>> easily adapt a morion. I can try it at least by starting with the morion >>>>>> on >>>>>> an >>>>>> external power supply and patching the output and control voltages in to >>>>>> the >>>>>> sr. >>>>>> >>>>>> The sr620 has a control circuit which apparently accomplishes your >>>>>> suggestions; they claim to use the internal oscillator for short term >>>>>> and >>>>>> "lock" it to a supplied external source for longer term. Probably has a >>>>>> long >>>>>> time constant on the built-in phase lock to do this. >>>>>> >>>>>> Anyhow, autocal calibrates everything except, guess what, the 10 mhz >>>>>> source. >>>>>> Thats done separately. >>>>>> So a bootup self check shows OK even if the frequency standard is way >>>>>> off. >>>>>> >>>>>> Onward and upward. >>>>>> Don >>>>>> >>>>>> Bob Camp >>>>>>> Hi >>>>>>> >>>>>>> I believe that the SR620 uses a “true” 10 MHz OCXO. I would be careful >>>>>>> using a >>>>>>> 5 MHz doubled to 10 OCXO. The counter may or may not be happy with >>>>>>> sub-harmonic induced jitter. >>>>>>> >>>>>>> Best bet at the specs: >>>>>>> >>>>>>> +12V power >>>>>>> 0-5V EFC >>>>>>> Sine wave out +7dbm >>>>>>> >>>>>>> +/- 5x10^-9 0 to 70C >>>>>>> >>>>>>> Pinout - trace what you have. >>>>>>> >>>>>>> Bob >>>>>>> >>>>>>>> On Nov 21, 2014, at 6:59 PM, Don Latham <[email protected]> wrote: >>>>>>>> >>>>>>>> >>>>>>>> So, I got a reasonable deal on a SR620 ho ho. Know your dealer. The >>>>>>>> ocxo >>>>>>>> is >>>>>>>> out of tolerance. All self tests pass with flying colors, autocal >>>>>>>> works >>>>>>>> as >>>>>>>> well. So the best parts are OK. >>>>>>>> Does anyone: >>>>>>>> 1) have a spare Isotemp OCXO36-53 10.000 MHz p/n 6-00051? >>>>>>>> 2) know the specs, ie the input voltage/current and the control >>>>>>>> voltage >>>>>>>> span >>>>>>>> and direction? pinout? >>>>>>>> I have some Morion mv-89's and could easily cobble one in if it will >>>>>>>> work. >>>>>>>> Apparently a correct oscillator must be in place to use an external >>>>>>>> source, >>>>>>>> if >>>>>>>> I read the manual right. >>>>>>>> >>>>>>>> 3) do we have a source for the schematics for the SR 620? >>>>>>>> >>>>>>>> The FTS 4060 is up, pumpin' and firmly locked. At least for now. That >>>>>>>> dealer >>>>>>>> was not lyin' >>>>>>>> >>>>>>>> Much thanks to all of you. >>>>>>>> The adventure continues >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> "The power of accurate observation is commonly called cynicism by >>>>>>>> those >>>>>>>> who >>>>>>>> have not got it." >>>>>>>> -George Bernard Shaw >>>>>>>> >>>>>>>> Dr. Don Latham AJ7LL >>>>>>>> Six Mile Systems LLC >>>>>>>> 17850 Six Mile Road >>>>>>>> Huson, MT, 59846 >>>>>>>> mail: POBox 404 >>>>>>>> Frenchtown MT 59834-0404 >>>>>>>> VOX 406-626-4304 >>>>>>>> Skype: buffler2 >>>>>>>> www.lightningforensics.com >>>>>>>> www.sixmilesystems.com >>>>>>>> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> time-nuts mailing list -- [email protected] >>>>>>>> To unsubscribe, go to >>>>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>>>>> and follow the instructions there. >>>>>>> >>>>>>> _______________________________________________ >>>>>>> time-nuts mailing list -- [email protected] >>>>>>> To unsubscribe, go to >>>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>>>> and follow the instructions there. >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> "The power of accurate observation is commonly called cynicism by those >>>>>> who >>>>>> have not got it." >>>>>> -George Bernard Shaw >>>>>> >>>>>> Dr. Don Latham AJ7LL >>>>>> Six Mile Systems LLC >>>>>> 17850 Six Mile Road >>>>>> Huson, MT, 59846 >>>>>> mail: POBox 404 >>>>>> Frenchtown MT 59834-0404 >>>>>> VOX 406-626-4304 >>>>>> Skype: buffler2 >>>>>> www.lightningforensics.com >>>>>> www.sixmilesystems.com >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> time-nuts mailing list -- [email protected] >>>>>> To unsubscribe, go to >>>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>>> and follow the instructions there. >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- [email protected] >>>>> To unsubscribe, go to >>>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>>> and follow the instructions there. >>>>> >>>>> >>>> >>>> >>>> -- >>>> "The power of accurate observation is commonly called cynicism by those >>>> who >>>> have not got it." >>>> -George Bernard Shaw >>>> >>>> Dr. Don Latham AJ7LL >>>> Six Mile Systems LLC >>>> 17850 Six Mile Road >>>> Huson, MT, 59846 >>>> mail: POBox 404 >>>> Frenchtown MT 59834-0404 >>>> VOX 406-626-4304 >>>> Skype: buffler2 >>>> www.lightningforensics.com >>>> www.sixmilesystems.com >>>> >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- [email protected] >>>> To unsubscribe, go to >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >> >> >> -- >> "The power of accurate observation is commonly called cynicism by those who >> have not got it." >> -George Bernard Shaw >> >> Dr. Don Latham AJ7LL >> Six Mile Systems LLC >> 17850 Six Mile Road >> Huson, MT, 59846 >> mail: POBox 404 >> Frenchtown MT 59834-0404 >> VOX 406-626-4304 >> Skype: buffler2 >> www.lightningforensics.com >> www.sixmilesystems.com >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > -- "The power of accurate observation is commonly called cynicism by those who have not got it." -George Bernard Shaw Dr. Don Latham AJ7LL Six Mile Systems LLC 17850 Six Mile Road Huson, MT, 59846 mail: POBox 404 Frenchtown MT 59834-0404 VOX 406-626-4304 Skype: buffler2 www.lightningforensics.com www.sixmilesystems.com _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
