| .....At
the time this set of notes were in use there was no cable TV and no Fiber
Optic cable. Coax cable had been in use for quite some time, being used
by AT&T for long lines service where Vern was not involved. T-screen
cable was in use which Vern was designing in small sizes.
.....Voice telephone transmission over copper paired cable has not changed to this day. It is still the lowest cost means telephone service and the most reliable, especially in rural areas. Cellular service is good too but still not perfect. .....Notice Vern had to use a factor to compute filled cable losses which was a better cable, helped keep water out with a better/lower transmission loss. .....Today's data requirements over paired copper is very limited. Only those subscribers within 8db of the Central Office are privileged to have DSL service. 8db is the same as 15kf of NL 26 ga. cable. If a service cable is degraded for some reason, the 8db limit point will be less than 15kf from the office. .....Vern has this problem, He can not get DSL on his paired copper service. .....Anyway - all the factors listed below are still good. January-27-2003
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