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krw[_3_]
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Surge / Ground / Lightning
In article ,
says...
krw wrote:
In article ,
says...
Mike Tomlinson wrote:
Phone wires were clamped to ground before the 1960s?
It was common to earth one leg of the incoming pair to either the house
ground or to its own rod. An earth connection also allowed "party
lines", where two houses could share one physical phone line pair, each
house with its own number. Disadvantage was that both lines could not
be used simultaneously.
http://en.wikipedia.org/wiki/Party_line_(telephony
)
I think they used to ring between the red green for one party, yellow
green for the other party, black green, etc.
No, that would defeat the purpose of the party line. The ringers
either had "distinctive ring" (once for Mabel, twice for Maude) or
were frequency tuned.
They did frequency and distinctive rings. But for 2 parties you can ring
red-to-ground for one and green-to-ground for the other. It is in Mike's
Wikipedia link above. My recollection is black was ground and yellow was
sometimes used for a light in the phone (red and green are phone wires).
Princess phones used the yellow green pair for the dial light. A
transformer was hidden somewhere in teh house to supply the power
(IIRC, a standard 24VAC door bell transformer, but it's been a lot
of years).
--
Keith
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