DL>Does the phone system actually have a 'ground' side, or is it
DL>a true balanced pair?
Neither. As I understand it, there's DC on the line always,
plus sometimes the audio AC (voice or dial tone, balanced).
The "ring" is caused by pulsed AC at ~ 100 V, which is why
you can get a notable shock if you're monkeying with the wires
when the phone rings.
Reggie Arford
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 X SLMR 2.1a X That's not line noise! My modem is speaking in tongues!
--- Maximus 3.01
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