[asterisk-users] UK (BT) Problem with TDM 400P

[Nick Chalk]

Mark Muffett <mark.muffett at gmail.com> wrote:
> I'm trying to get my TDM400P to work with a BT
> POT line.
....
> when I connect the FXO unit to the BT line it
> just makes it (the BT line) go permanently
> engaged.
....
> has anyone ever managed to get a TDM400P to work
> with a BT line and did they have any of these
> issues?

Yes, I had a test system with a TDM400P and two
FXO modules terminating two BT Featureline Compact
lines.

However, "had" is the operative word.

One of the two FXO modules is now holding the line
permanently off-hook - even when the system is
powered down. The other module is fine, and the
drivers don't see anything wrong with either
module.

My suspicion is that the one module is dead. I
haven't had a chance to pull out the machine and
play with it, though.

To see if you have a similar problem, connect a
phone in parallel with the FXO module. Unplug the
module from the line, and check that you get a
dial tone with the handset. Hang up, and plug the
FXO back in. Then lift the handset again - I get a
noisy line with a very quiet dial tone. If you
wait long enough, the dial tone will stop and
you'll hear the screamer, again very quiet.

I've no idea what caused our fault. I don't know
of any storms before the failure, and all the
other connected equipment is fine.

Nick.

-- 
Nick Chalk ................. once a Radio Designer
 Confidence is failing to understand the problem.