and, yes, if your 'scope has the 50ohm/1Mohm input capability, use the 1M one.
On Sun, Nov 25, 2012 at 12:03 AM, Azelio Boriani <[email protected]>wrote: > Usually the PPS output from the Z-series GPSDO is a 26uS wide (from the > HP58503A datasheet) TTL pulse. To measure it you must use a fast > oscilloscope (because of the fast pulse rise time) and an analog or digital > memory (because of the very low repetition rate). The best is to use a > digital sampling 'scope and set the trigger to NORMAL. > > > On Sat, Nov 24, 2012 at 11:42 PM, Mark Spencer <[email protected]>wrote: > >> Greetings. I recently acquired two Z3805A gpsdo's from the usual >> auction site. (These units look like a Z3801.) >> >> Does any one know the specified output level for the 1pps signals or have >> a high confidence measurement of the output voltage that they could share >> with me ? (Measuring fast rise time signals is not really my forte and I >> don't trust my measurements of an apparent .15 volt pulse.) >> >> The status message sent from the units via RS 232 contains a TFOM ( time >> figure of merit ?) variable and I've seen that phrase used in conjunction >> with equipment that outputs a 10 volt 1 pps pulse. >> >> On a side note so far I'm pleased with the performance of the units (the >> 10 Mhz output of better of the two has a typical adev in the low 10e-12 - >> high 10e-13 range, and appears to be improving.) >> >> Thanks in advance for any comments. >> >> Regards Mark Spencer. >> _______________________________________________ >> 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.
