[time-nuts] Timing Distribution in Mountainous Terrain

[Hal Murray]

ralph at ralphsmith.org said:
> There are probably several fatal flaws with this approach. In particular,
> the following are required:
> 1) Ability to maintain constant lock to WWV
> 2) Common-mode error. Will the propagation from WWV be similar
> enough for all stations to it be a practical common reference.
> 3) Adequate resolution. Even if, for some reason 1 and 2 are possible,
> would the result be good enough to use. 

My quick guess is that WWV would be worse than LORAN since LORAN got to pick 
the frequency that would work best.

If you want more info, you probably need to contact a radio propagation 
wizard.  Unless you are very close, the signal will be bouncing off the 
ionosphere and that isn't stable.  There are big changes from day to night, 
and I think you can measure the tiny changes during the day if you have a 
good clock at the receiver.

Didn't one of the recent FMT discussions mention something like this?  I 
think they were measuring a frequency shift which would translate into 
velocity of the layer.

Dave Mills has drivers for NTP that decode WWV/H signals from a short wave 
radio going into a PC audio chip.
  http://www.eecis.udel.edu/~mills/ntp/html/drivers/driver36.html
In general, he's getting sub ms rather than few ns.


-- 
These are my opinions, not necessarily my employer's.  I hate spam.