Dear Bruce, Time-Nuts, Sorry for the "silence" it was a long weekend. I checked the oscillator, the serial number was: 1528A10107
If I'm correct this means it was manufactured in week 28 of 1975. A pity that the cold frequency-offset is nowhere metioned, except for the HP-Journal article. Best regards, Jeroen Dr Bruce Griffiths wrote: >Jeroen Bastemeijer wrote: > > >>Dear Time-nuts, >> >>New info on an old subject: >> >>I opened the counter (5345A) to check what kind of oscillator was >>inside. It was a 10544A instead of a 10811A!!! >> >>I checked for a datasheet of the 10544 but I couldn't find it. Luckily I >>ran across an article in HP Journal. See the quote below: >> >>Warmup. The 10811A/B Oscillator cuts the 10544/B/C >>warmup time specification in half: 10 minutes for the >>10811A/B compared to 20 minutes for the 10544A/B/C Oscillator. >>Warmup time is defined as the time between oscillator >>oven turn-on and the time when the output frequency >>is within 0.05 Hz of the operating frequency, In portable >>instruments, where battery weight must be minimized, low >>power and quick warmup are crucial. Since the instrument >>warmup time is likely to be much shorter than the oscillator >>warmup time, the latter usually dominates. A side benefit of >>the 10811A/B is that its frequency just after oven turn-on is >>only 100 Hz low compared to 1 kHz low for the 1054aA/B/C. >>This allows faster lock-in for instruments using phaselocked >>loops. >> >>Bottom line: The 10544 gives a higher offset at switch-on compared to >>the 10811. >> >>Only thing to do now is find a datasheet to verify it with real numbers, >>as my oscillator was 1700 Hz off (compared to 1 kHz in the article) and >>Didiers' oscillator was 200Hz off (compared to 100 Hz in the article). >>Is there a link to the 10544 datasheet somewhere out there??? >> >>Have a nice weekend, Jeroen >> >> >> >> >Jeroen > >There are at least 2 versions of the 10544A. After the initial >production models modifications were made to improve the phase noise specs. >The oscillator, oven controller and oven supply volatage specifications >also changed after this modification. >I have a set of datasheets dated: 1 October 1972, July 75, July 1976. >There is no specification on the datasheet for the frequency offset at >startup with a cold oven. >Any idea when your oscillator was manufactured? > >Bruce > >_______________________________________________ >time-nuts mailing list >[email protected] >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > > -- Ing. Jeroen Bastemeijer Delft University of Technology Department of Electrical Engineering Electronic Instrumentation Laboratory Mekelweg 4, Room 13.090 2628 CD Delft The Netherlands Phone: +31.15.27.86542 Fax: +31.15.27.85755 E-mail: [EMAIL PROTECTED] _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
