In article , Joseph Fenn writes:

How in the hell can the CLOCK detector tell any difference between
the time signal from WWV or WWVH. They are both on exact same
frequecies, the time tick is identical on both !!!!

Not "identical." See -

http://www.boulder.nist.gov/timefreq...orm.html#timea

The "tick" sounds the same from each station but is different in
the frequency inside the burst.

Len Anderson
retired (from regular hours) electronic engineer person