[Nottingham] HylaFax

Peter Woods peterwoods at f2s.com
Wed Oct 22 17:04:35 UTC 2008

Matt Jones wrote:
> Hi martin.
> I am using Suse Linux Enterprise 10.0.
> The modem us running to an Avaya VOIP system which runs to a ISDN 30  
> circuit.
The Avaya interface may be your problem.
The "line circuit" on new equipment often tries to be clever and save 
heat, power, etc
by providing a constant current (as opposed to a constant voltage like 
the old stuff.)
UNFORTUNATELY, if the modem is trying the same trick you will get ZILCH.
(The modem should, of course, provide a constant resistance to the 
constant voltage from the "exchange".)
Two constant current devices will fight each other and one will not 
saturate, hence no voice-band signal.
This used to be a problem (occasionally) about 5-8 years ago,
but may be more or less prevalent now (since I left the telephone industry.)

I would try the modem in other telephone lines.
It might be a long shot, but if that IS the problem, you are bu**ered.
It is fairly unlikely the modem has any kind of internal setting to 
avoid this.

HTH and that's not your problem

Pete Woods

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