[time-nuts] Timing on Ethernet

Poul-Henning Kamp phk at phk.freebsd.dk
Sun Aug 5 12:13:41 EDT 2007

In message <200708050858.47945.bob.paddock at gmail.com>, Bob Paddock writes:
>); SAEximRunCond expanded to false

>We found the best "waveguide" experience was in
>the range of 300 to 420 MHz, but the distance is very limited,
>hundreds of feet at most.  The main problem at different frequencies
>is the material becomes absorptive at lower frequencies,
>or reflective at higher frequencies causing to much mutilpath

Most mines are in coal or metalrich rock, wouldn't that make
your experience more pessimistic than the tunnels at CERN which,
as far as I remember, is in pretty 'worthless' rock ?

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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