[time-nuts] 10 MHz 'failover' switch?

[Chris Caudle]

On Thu, July 26, 2018 5:05 pm, Hal Murray wrote:
> Has anybody built a microprocessor controlled PLL to handle this case?

There are failover clock generators (integrated circuits), typically
marketed for use in telecom equipment where there is a requirement to
synchronize with a reference clock if it is available, and if the
reference clock is not available for some reason flag an alarm and
continue running from a local oscillator.
As pointed out, not necessarily "time-nuts" quality of close in phase
noise and ADEV performance, but you can do handy things like have
controlled slew on the output of the PLL so that there is no sudden phase
jump when the reference clock goes away.

-- 
Chris Caudle