[time-nuts] Divider circuit for Rubidium Standard

[Richard (Rick) Karlquist]

>
> The only gates that seem to do very well are high speed (as in 74AC or faster)
> silicon CMOS. You need to run them with a fairly clean supply and feed them
> with a p-p input that matches the supply voltage. Other than that, not a lot
> of magic. Are they ideal - surely not. Will they hit 2x10^-13 ADEV at 1 second and
> drop from there as tau increases - yes they will.
>
> Bob
>

Interesting.  Back in the stone age in 1990, 74AC was state of the art.
As soon as it came out, I used it exclusively for everything that didn't
require ECL, for which I used ECLinPS exclusively.

In the 5071A, we used one to square up 80 MHz for the DDS board.  You
are exactly right:  put in a huge sinewave obtained by good old
fashioned analog anplifiers and let the 74AC do its thing.  80 MHz
is pretty much flat out for a 74AC series. The 80 MHz came from a
10 to 80 MHz multiplier running from the 10811.

Rick Karlquist N6RK