Luca, I am using a HP3575a phase and gain meter good to 1Hz-13 MHz but easily goes to 15 MHz. It delivers a dc voltage that feeds a DATAQ 4 cnl USB A/D coverter and chart program $25. Its been working very well for comparing references long term. Just suggesting the 3575 as a possible alternative. Good luck Regards Paul WB8TSL
On Sat, Jan 30, 2016 at 5:52 PM, Alex Pummer <[email protected]> wrote: > Hi Luca, > look here: http://www.clmt.de/service-manuals/ > 73 > KJ6UHN > Alex > > On 1/30/2016 12:49 PM, Luca Dal Passo wrote: > >> Hi All, >> while i was looking for an hp k34-59991A phase comparator on ebay in >> order to make some long term measurements of frequency drift of a dut >> against a reference (by logging the analog output of the meter) i found >> and >> bought a Bruel & Kjaer type 2971 phase meter instead of the hp. >> It is a very nice unit, with digital and analog readout, high resolution >> and high precision. >> The drawback is that it is a very low frequency device, specified for the >> range 2Hz to 200 kHz. >> So, to compare two 5 or 10 MHz signals i'm thinking to use two simple >> double balanced mixer, some low pass filtering on the IF outs of the >> mixers, and a common local oscillator of about 5,1 MHz or 10,1 MHz to >> convert signals into the range of the instrument. >> The actual frequency of the local oscillator does not metter, because it >> is >> the same for the two input signal, and theoretically i could use even a >> simple free oscillator, provided only the frequency falls in the correct >> region regardless of phase noise and stability because their effects are >> subtracted cancelling themselves. Anyway i think to use a simple ambient >> temperature xtal oscillator for that. >> What are your opinions? What i'm forghetting to consider? What kind of >> drawback i have to expect? >> The other question is about the availability of user/service manual (or at >> least schematics) of the Bruel & Kjaer 2971: i'm not able to find >> anything >> on the net. >> Many thanks! >> Luca >> IW2LJE >> _______________________________________________ >> 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. >> >> >> ----- >> No virus found in this message. >> Checked by AVG - www.avg.com >> Version: 2016.0.7357 / Virus Database: 4522/11519 - Release Date: 01/30/16 >> > > _______________________________________________ > 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.
