[time-nuts] 5370B arrived - any FAQ

wje wje at quackers.net
Thu Jun 19 13:01:28 UTC 2008


   Why, you use your 8082A! I got one for a steal a couple of years ago on
   EBay.
   However, all you really need is a fast rise-time pulse generator that
   has external triggering and a variable trigger delay, and can generate
   a +1/-1 volt swing. The frequency the tests use aren't that critical,
   anything 1Mhz or higher should work. The only semi-critical parameter
   is the rise time; the faster it is, the less trigger uncertainty you'll
   have. 1ns is good. :) Also, unless the delay time setting is rather
   fine, it's extremely difficult to actually do the anti-coincidence
   alignment.
   What I'm missing is a spectrum analyzer, so I haven't done the
   frequency multiplier alignment on either of my 5370s. Any tricks for
   doing that without one?
Bill Ezell
----------
They said 'Windows or better'
so I used Linux.

   Chuck Harris wrote:

wje wrote:



Freq vs time interval - simplistic answer: when you're using
time-gating, you're looking at more samples than in averaged one-period
mode. For 10Mhz, a gate of 0.1 secs is 1 million periods. In period
mode, you're averaging a maximum of 100,000 periods. Accuracy is
proportional to the square root of the number of samples.


Also, the trigger point jitter when in one-period mode affects every
sample, but when in gate mode it only affects the first and last
cycle.


The 'specifications' section of the manual gives the formulas for
determining both resolution and accuracy (which are NOT the same) for
the various modes.

I would suggest you go through the detailed alignment procedures even
though the unit passes the operational checks. These units almost always
have drifted out of alignment in the analog front-end unless you were
lucky enough to get a freshly-calibrated one. You can usually
significantly improve channel-to-channel trigger consistency and lower
the jitter by doing so.


What does one do where the tests call for an HP8082A pulse generator?
The silly things are so rare that they are priced in the stratosphere!

-Chuck Harris

_______________________________________________
time-nuts mailing list -- [1]time-nuts at febo.com
To unsubscribe, go to [2]https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.

References

   1. mailto:time-nuts at febo.com
   2. https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts



More information about the Time-nuts_lists.febo.com mailing list