[time-nuts] 5370B arrived - any FAQ

Chuck Harris cfharris at erols.com
Thu Jun 19 08:18:10 EDT 2008

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
> 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

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