I was using an HP 5370B (resolution of < 50 ps - yes picoseconds) referenced to my Efratom FRT Rb standard.
Very nice, wish I had one of those in my lab
Actually, that's not my best time interval measurement tool.
https://www.eevblog.com/forum/testgear/wavecrest-dts-2077-teardown/msg279391/#msg279391
Ed
I assume that you figured out how to use it, can you show us what it does.
It's a Time Interval Counter. It measures frequency, time from A to B, rise time, fall time, period, pulse width, etc. But it does it *really* well!
I've been struggling to extract its full potential because it needs an input with very sharp rise and fall times. Forget 10 MHz, even 100 MHz isn't really enough, 1 GHz is okay! I built a circuit to square up a 5 or 10 MHz signal so that it can be properly measured, but it needs a little more work.
One of the particularly neat features is called a "strobing voltmeter". It allows you to sample the input at time intervals as small as 10 ps and report the results. In other words, it's digitizing the signal at 100 Gs/s.
I threw together a proof-of-concept program to test this. The attached picture is the output from my squaring circuit. Due to limitations in the strobing voltmeter, it took me quite a while to figure out how to get this picture. Initially I didn't think I would be able to do it. The horizontal scale is in units of 100 ps. The vertical scale is in volts. The voltage is small because the maximum voltage on the input is only 1.7 volts. I
really don't want to blow the input on this thing!
Ed