On 7/6/2016 9:56 AM, J.B. Wood wrote:
On 07/06/2016 12:29 PM, mike wrote:

Neighbor had a similar problem.
Turned out to be a busted ground wire half a mile away.
The local ground connection was enough to make the audio
work, but the broken wire made the other stuff fail.

Hello, and interesting. By "ground" do you mean earthed? In the olden
all-analog days IIRC the only connection to earth on a 2 wire phone line
was at the CO where the positive terminal of the 48 volt common battery
was solidly connected to earth. (I'm not including party-line
ringing-to-ground configurations that are decades obsolete.) Sincerely,

There are two wires. One is grounded, the other has -48 volts.
If you cut the grounded wire and use a voltmeter to measure
the voltage to ground at the customer end, you measure -48 volts to ground,
but the signal is trying to use one wire and the local ground
path that it could find.
That didn't work for phone, but it did work for DSL,
although I didn't measure the speed or error rate.
I was gonna TDR the line, but was afraid the phone might ring
and blow up my instrument.
The phone guy took a quick look and drove away.
Came back in half an hour and said the ground wire had
been severed down the street.