frank1492 wrote:

I have two phones and a modem which I have tried disconnecting.
I did not disconnect the house wiring at the box but will try
when I get the time. I do not have an alarm system, but I do
have a standalone answering machine, which I thought I had ruled
out but will check again.

Uh hu. Ok, so any other devices? Fax machine maybe?

Actually I thought the jack at the interface wasn't supposed to
require any of that. Although I am not an expert on interfaces
I have never had Verizon tell me that I would have to disconnect
my home wiring in order for that test to be reliable. Perhaps you
could explain further.

Typically the exact "demarc" point is a modular jack or terminal block
mounted to the wall, probably near to where your electrical service
panel is. All the phone jacks in your house are wired to this demarc.

The demarc might look like one of these:

http://upload.wikimedia.org/wikipedi...px-Demarc2.JPG
http://www.maximumpc.com/files/u1124...rc_before2.jpg
http://flylib.com/books/2/545/1/html...ges/f27-11.jpg

You have a condition where you're not getting a dial-tone, but your DSL
service is still working. Most likely there is a device (phone, fax,
answering machine, possibly even the DSL modem itself, or a DSL filter)
that is causing an "off-hook" condition. It's like the handset of a
phone that's hidden somewhere in your house was lifed off it's cradle
and just left like that - off hook.

I don't believe you've said if there is a phone jack at your demarc
point. Ideally there should be - the rest of my instructions will
assume you have one there.

Your phone service is supplied by 2 wires (typically red and green).
You might 4 wires in total coming in from the outside (red, green, black
and yellow). Locate the two that are connected to your home's phone
wires. Or you might have just two wires (both of them black).

Once you've located the two wires that are connected to your home's
phone wires, its only necessary to disconnect one of those wires from
your home's phone wiring (but not to the service jack that should be
located nearby). This means your DSL modem will also be cut off and you
will lose your internet connectivity (but only for as long as this wire
is disconnected).

Once you do that (disconnect one wire) you've effectively cut off any
problem device from the incoming phone line, and the line should return
to an "on-hook" condition. Now at this point you need to have a known,
good working phone (how you determine that might be trial and error, or
plug it into a friend's or neighbor's house and verify that it works).
Take that phone and plug it into the jack at your demarc point (assuming
there is one). If there isin't one, if your handy with a screwdriver
then you should be able to connect an ordinary phone jack to your
incoming phone line, and remember to keep the rest of your home's phone
wires disconnected from the incoming line.

Once the known-good working phone is connected to your incoming phone
line, lift up the handset and see if you have a dial tone. If you have
one, then you've just established that a service call from the phone
company is not required, because the problem with with some device in
your home - or even with the wiring itself.