I would like to add my 25 cents worth and it is mostly about line noise.
back in the fifties and early sixties, our local power companies were
using 4,150 volt
delta 3 phase supply lines. That's 2400 volts to the pole pigs. now a days,
frequently without insulator upgrades, that voltage is 33,000 volts on
the 3 phase transmission lines and 19.9 kv to the pigs. cross country
lines were 115kv, now they are 670 kv. You may think
that the old clear channel AM radio stations have packed it in in favor of
FM, but next time you have an ice storm or hurricane, and all the AC
service has
been disabled, take a listen to a portable AM radio. They are still there
in all their glory. The problem is a general increase of line noise
averaging as much as 8 S units. and , alas unless you live on a mountain top
or in a desert, the "good old days" are forever gone because of
noise floor increase. Al K2MPE
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|