[time-nuts] is there a "best bet" advanced hobbyist buildable GPSDOdesign?

[christopher hoover]

> What I use on the reflock II is a time lag counter from the 1pps to
> next clock, and this value drive a dac. Only a small integration time
> is done digitally and the large integration time if one requires that
> is done with a classical R and C without any active components right
> before the Vtune of the VCXO. 

The problem with reflock II as I recall for use with a 1PPS (w/sawtooth)
from a GPS receiver, is that the time constant is way too small.  You can't
integrate to a point anywhere near the Allan intercept of the receiver and
the XO.

-ch