[time-nuts] Measuring 10 MHz accurately.

[Jim Lux]

At 10:20 AM 5/7/2008, Ulrich Bangert wrote:
>Martyn,
>
>2 parts in 10E-12 in a second's gate time would require to measure the
>time interval with an 2 ps resolution. Since the SR620 (at least mine)
>features a 20 ps single shot resolution, i fear your number is more
>likely "20 parts in 10E-12". Or what you are doing is to make >= 10
>measurements / s of phase and computing the arithmetic mean of them.

For example, the implication is that the SR620's timebase is accurate 
to parts in 1E-12 or 1E-13, so that it can count off that 1 second 
with suitable accuracy.