[Asterisk-Users] offtopic - channel banks

[Steven Critchfield]

On Sun, 2004-09-05 at 03:10, Ilia Mirkin wrote:
> hi,
> 
> i have some newbie questions about channel banks. i have an adtran
> act-1241 sitting around. it accepts D4 modules, and it contains a number
> of e&m cards.
> 
> first of all, how does this thing work? a t1 contains 24 channels, and i
> noticed that the channel bank has space for 24 cards. what do these
> cards do? what are their outputs? the ones that are in there have some
> outputs on the front marked "test", but nothing else. there are a number
> of wires coming out the back (48, if i had to guess), and it has a few
> ports on the front which seem to be able to take in a T1. am i correct
> in understanding that it is the card in the bank that determines the
> signalling style, and not the t1? as such, is there no way that i could
> use it in its current configuration to have it talk with analog phones
> (i.e. something like t100p -> act-1241 with e&m cards -> phone)? i'm a
> bit unclear on the different signalling types, and their
> intercompatibilities.
> 
> if anyone could shed any light into this, i would very much appreciate
> it.

Think of the T1 as 24 digital digital pathways. The coding of each
pathway must be compatible on each end. With E&M cards, you signal with
E&M and the line will work. The cards plug into a backplane where the
controller routes the digital signal to the card and then optionally
hook up the output from the card to a connector that consolidates many
lines. Look for something that looks like an older 50 pin scsi D
connector. 

If there is 2 RJ45 jacks on the front, and 2 50 pin D connectors on the
back, then it is likely that each card controlls 2 lines each. If there
is only 1 50 pin connector, then there is only 24 channels.

Hope that helps. 
-- 
Steven Critchfield <critch at basesys.com>