On Sun, 13 Jul 2008 11:57:25 -0400, mm
wrote:

On Sat, 12 Jul 2008 09:30:32 -0500, Art Todesco
wrote:

wrote:
That is what you report to your telephone provider. It is likely that
the "ring generator" for your line has died.

Yep...the phone rang this morning, and it was AT&T saying a box had
been hit by lightning and some fuses were knocked out.

Weird...I always though phones were all or nothing. I didn't know it
was possible for them to work but not be able to ring. Live and
learn.
That may have been true in years gone
by, however, everything now is
on circuit boards including your line
circuit and access to switching and
ringing. Ringing is special because it
is high voltage and must be applied

High voltage compared to the usual 12 volts.

About 80 volts AC iirc.


Here I see 50VDC on an "on-hook" phone line, ringing adds 75VAC, so
the voltage would be varying from -25V to +125V.

to the line metalically. Voice, on the
other hand, is usually converted to
digital and then switched as a bit stream.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy