Re: 11801 NVRAM

Albert Otten

On Tue, Sep 17, 2019 at 12:43 AM, Reginald Beardsley wrote:

I am reporting what the frequencies of the trigger and ramp generated by the
33622A are and what the time/division of the 11801 is set to. The 33622A
frequencies are accurate to more digits than I have shown. ~1.1 ns is the
difference in the length of the trigger clock period and the ramp period. The
33622A is *much* more stable than the 11801 clock.
OK Reg, but I still can't understand how this would work.
I suppose each trigger event results in a sample. At each trigger event the position on the ramp advances 1.1 ns when compared to the previous trigger event. Over 1024 events this advances the position over about 1.1 us. Meanwhile there is also a total advance of 10 ps in the position of the sampling event due to the increases of delay between sample and trigger event; but 20 ps is negligible compared to 1.1 us. So I expect you can see only 1/9 fraction of the total ramp, which would also run vertically.
In my own experiment I found about 10 ns difference between required periods.

[BTW w.r.t. sweep jitter: this is not related to the blinking light at the sampling head, what has been recognized as cause of slight sweep jitter?]


Join to automatically receive all group messages.