[Asterisk-Users] TDM400P specs clarification

[varun_saa at vsnl.net]

----- Original Message -----
From: Rich Adamson <radamson at routers.com>
Date: Monday, January 31, 2005 5:42 pm
Subject: Re: [Asterisk-Users] TDM400P specs clarification

> > Hello,
> >       I need some clarification on TDM400P.
> > 
> > While browsing the Digium site I see that the TDM400P wildcard 
> > is being used as base card for other TDM series cards.
> > 
> > I wanted to know what basically the TDM400P card offers. 
> > If you see the specs it says :
> > 
> > " The Wildcard TDM400P is a half-length PCI 2.2 compliant card 
> > that supports from one to four telephone interfaces for 
> connecting 
> > analog telephones or analog lines to a PC "
> > 
> > The term : 
> > 
> > " one to four telephone interfaces for connecting 
> > analog telephones or analog lines "
> > 
> > In terms of FXO and FXS what does it mean. I can see that
> > it has four RJ 11 sockets.
> > 
> > How will you decide which of the four interface to use for
> > what. I mean FXO or FXS.
> 
> The fxo modules are designed to interface to a pstn line (where
> ringing comes from the central switching office).
> 
> The fxs modules are designed to have standard telephone sets
> plugged into them, and the module provides ringing voltage to
> the telephone.
> 
> On the digium web site, a tdm04b is the tdm card with four fxo
> modules installed. The tdm40b is the same tdm card with four
> fxs modules installed. The tdm22b has two fxo and two fxs modules.
> 
> If you incorrectly connect a fxs module to a pstn line, you will
> likely blow the module making it useless.
> 
> 

That was very helpful, Thanks

Varun