[Asterisk-Users] Questions about AGI and Wildcard boards

[Don Pobanz]

On Monday, May 19, 2003 6:05 PM, Mike Atkinson 
[SMTP:silverflash at bancclub.net] wrote:
> > Back when I worked at the phone company it was a common occurrence
> > to
> > multiplex analog DID trunks. So, analog DID trunks should be able
> > to
> > interface * after they are multiplexed using a channel bank. (the
> > channel bank needs to support DID trunks!) The T1 side of the
> > channel
> > bank would interface with a T100P or T400P board from Digium.
>
> Don,
>
> Are you saying that they are multiplexing these analog lines (which
> SBC
> tells me is a modified POTS line) and feeding them in channelized on 
a
> T1?

Phone companies provide DID trunks from the trunk side (not the line 
side) of a telephone switch. Nowadays these are only provided in a 
digital format (part of a T1). In order to deliver them as analog DID 
trunks the phone company will use a channel bank, usually back in the 
central office to convert them. As analog DID trunks they require a 
cable pair for each trunk. This would be your 4 pairs.

> Interesting since a regular analog handset works on them and there
> appear to be 4 pairs of wire.
>

For this part my expertise is starting to fail so if anyone sees 
anything wrong please jump in.

Do you get dial tone from the analog handset?
Can you make calls with an analog handset?
You should be able to do these for pots lines or analog DID trunks 
which use loop start. Ground start  DID trunks would not give you dial 
tone.

For more information see http://www.ct-labs.com/Dr%20C/q47.htm

Will the handset ring if called?
I don't believe it would for trunks.

Regardless, after a call is received, the phone company would then 
forward digits for the extension that was dialed. These should be in 
the form of DTMF tones (Dual Tone Multi Frequency).

Good luck!

> I'm not doubting what you are saying, but I want to understand what 
is
> going
> on so I can make better decisions as I go along :)
>
> Thanks!
> Mike