[Asterisk-Users] Adit 600 channel bank in UK setting

[Peter Hoppe]

Hello!

I am projecting a replacement telephone system for a small organization 
in the UK. Our old pbx is showing signs of age and will probably soon go 
into pension.

The old system consists of a mix of 4 wire lines terminated with 
proprietary telephones and 2 wire lines with standard 2 wire telephones. 
The system connects to the PSTN via three BT lines.

I would like to replace the old system with an asterisk based system and 
would like to implement it as a hybrid solution containing IP phones and 
standard 2 wire phones. At present we have got a small experimental 
setup that has got Asterisk running on SuSE Linux 9.0 with two 
Grandstream BT100 IP phones and one 2wire phone on a Grandstream 
HandyTone 286 adapter which I use. The Asterisk box is connected to a BT 
line via a Digium Wildcard X100P card.
If we do internal phone calls we have no problem with any connections. 
However, outgoing calls are somewhat different - No problems have been 
reported with the BT100 telephones, but the HandyTone connection has 
some problems:

*    When I get the outside (PSTN) line and dial a number, I sometimes 
get connected to the wrong number.
*    At one time I had a conversation and after about 20 minutes there 
came a pulsating noise which slowly increased until I couldn't hear the 
other party any more and had to stop the conversation and phone the 
person via the other pbx.
*    I tried different phones on the ht adaptor but only one phone rings 
when I get a phone call.



At present the plans are:

* The IP phones are connected to a switch and the switch is connected to 
the asterisk box via a network card. The asterisk box would be a 
standard PC with Asterisk running on SuSE Linux 9.0.

* The 2wire phones are connected to a channel bank and the channel bank 
has got a T1 port which is connected to the asterisk box via a T1 card.

My question concerns the channel bank. We would like to use a Carrier 
Access ADIT 600 with

* 1 dual T1 controller card
* 1 230 VAC/-48 VDC Power supply/charger card
* 5 fxs 8 channel voice service cards (which allows us to connect up to 
40 telephones)
* 1 fxo/dpt 8-channel voice service card (to connect the three BT lines; 
a bit of a waste, but I couldn't find an fxo card with less fxo ports).


To connect the channel bank to the asterisk box we would equip that box 
with a Digium Wildcard T100P card and use a cable terminated with RJ48 
plugs on both ends.

My questions are:

* Is it legal in the UK to connect an Adit 600 channel bank (with the 
fxo card) to a BT line (PSTN)? In the technical specification sheet that 
I downloaded from the carrier access website there is mention of 
different regulatory approvals:

- FCC Part 68, CS-03 (not registered for connection to the PSTN)
- FCC Part 15, ICES-003 Class A
- NRTL safety listed: UL 1950, CSA C22.2 No. 950
- NEBS Level-3 certified as type 2 and 4 equipment (Intrabuilding)
- TelcordiaTM GR-63-CORE, GR-1089-CORE

If not, does anyone know of another legal way to bring three BT lines to 
an asterisk box?


* Has anyone noticed problems connecting UK PSTN lines to the channel 
bank with the aforementioned fxo card?  Would dialling work 
satisfactorily? What about ringing when outside calls come in? What 
about the audio quality? Would prolonged conversations be sustainable?


* Has anyone noticed problems connecting standard 2wire phones to the 
channel bank with the aforementioned fxs cards? With standard 2wire 
phones I mean phones that one can buy in any shop. We had some question 
marks over this issue because of the problems with the handytone adaptor 
- but my personal opinion is that there is a world of difference between 
the channel bank and the ht adaptor; however, we need to be sure of that.


* Is it conform to the UK standard to use a T1 connection between 
asterisk and the adit 600, or should we rather use an E1 connection? We 
want to avoid locking ourself into having to buy spare parts from the US 
in case the T1 connection breaks down. Can we get T1 cards in the UK or 
would people rather recommend E1? The Adit 600 can also be equipped with 
a controller that has 2 E1 ports.


Thank you very much for your considerations!



-- 
There are 10 kinds of people in the world,
those who understand binary, and those who don't.