[time-nuts] Timing Distribution in Mountainous Terrain

[Stanley Reynolds]

~ 1ft  = 1 ns for coax, but 1000-2000 us is common delay for long phone lines 
which is very frequency dependent, you would want unloaded circuits, loading 
coils would make for more problems. My experience with metallic circuits is 
limited to less than 10 miles at some point you would need an 
amplifier/repeater. I do know noise and cross talk and other impairments are 
common. Data modem design is quite complicated but I don't think they are very 
predictable as far as delay goes, except delay increases and transfer rate 
decreases with impairments.

Stanley 



----- Original Message ----
From: J. L. Trantham <jltran at att.net>
To: Discussion of precise time and frequency measurement <time-nuts at febo.com>
Sent: Fri, September 10, 2010 9:09:29 PM
Subject: Re: [time-nuts] Timing Distribution in Mountainous Terrain



-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Stanley Reynolds
Sent: Friday, September 10, 2010 7:13 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Timing Distribution in Mountainous Terrain


How to keep hundreds of miles of copper stable or predict it's delay ?

Stanley



Would temperature changes over any consecutive 6 day period create a 30 nS
change (assuming the 'central station' is indeed central)?  

And, if so, would that make any difference in position accuracy since all
stations would have the same or similar error?  Oops, there I go again
thinking as a 'user' :>).

Joe


_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.