Hi Azelio, Sorry, the counters are 53131A, not 53151A. The A and B inputs are specified from DC to 225 MHz with a sensitivity of y20 mV (rms) up to 100 MHz, <30 mV (rms) 100 ~ 200 MHz, and <50 mV (rms) 200 ~ 225 MHz. The problem can be at either input alone. The problem is only in the range between 100 MHz and <200 MHz, observed in automatic trigger mode. In manual trigger mode the counter does not trigger at all in that freq range.
I cannot tell you an aging model for a particular OCXO, and I doubt if anyone can ;) Aging predictions can only be made on individual OCXO, unit by unit, and the prediction is only valid over a rather limited time. Therefore you must continuously monitor and update your prediction. Best regards Bernd DK1AG -----Ursprüngliche Nachricht----- Von: [email protected] [mailto:[email protected]] Im Auftrag von Azelio Boriani Gesendet: Freitag, 24. August 2012 17:28 An: Discussion of precise time and frequency measurement Betreff: Re: [time-nuts] HP/Agilet counter 53151A trigger problems >From the datasheet: A input 10Hz..125MHz min level 25mVrms (-19dBm) B input min 50MHz, -20dBm the problem is on A input only? Maybe 150MHz for the A input, being beyond the official specifications, requires more signal on one counter than the other. In the past they all were fine? I have read your paper on the correlation between the real and predicted aging of crystal oscillators. I'm trying to find a suitable model for the Morion MV201 OCXO or the Oscilloquartz 8663 to implement a Kalman filter. On Fri, Aug 24, 2012 at 3:34 PM, Bernd Neubig <[email protected]> wrote: > Hi all, > > I have several HP/Agilent frequency counters 53151A (and 53152A) in my lab. > Several of them meanwhile show trigger problems. > > I have tested the A and B channel between 5 MHz and 200 MHZ at three > input levels of -10 dBm, 0 dBm and +10 dBm. > > Those with trigger problems show erroneous numbers at -10 dBm input > level rather selectively, i.e. mostly at 100 MHz, some also at 150 > MHz, while the are o.k. > > Has anyone on this list experienced similar defects and can give a > recommendation how to fix/repair them? > > > > Best regards > > > > Bernd > > DK1AG > > www.axtal.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. _______________________________________________ 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.
