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

[ed breya]

Getting great isolation at 10 MHz is the easy part, given enough 
switching elements and control. One question is whether the switchover 
needs to be transparent (glitchless), without adding or losing any clock 
cycles, and ideally with no phase shift. This would involve a much more 
sophisticated system, with two or more redundant references locked 
together, at least short-term.

Ed