[time-nuts] Cycle jumps in Z3801A PPS?

John Ackermann N8UR jra at febo.com
Mon Jan 29 17:04:58 EST 2007


I'm looking at the PPS output of my pair of Z3801As.  One of them
generates a nice plot with about 50ns peak to peak noise over 1 day
(measured against a 5061A).  You can see that data at
http://www.febo.com/time-freq/plots/cs1-z3801a_1.html.

However, the second unit seems to have random jumps, usually for just
one PPS sample and occurring once every hour or two, of very close to
100 nanoseconds.  You can see what I'm talking about at
http://www.febo.com/time-freq/plots/cs1-z3801a_2.html.

Since 10 MHz has a period of 100 ns, I'm guessing that this jump
indicates some sort of one cycle slip in the PPS generator.

Has anyone else seen this behavior?

John



More information about the time-nuts mailing list