[Asterisk-Users] Some more hardware and E1 questions

[Peter Svensson]

On Mon, 24 Jan 2005, Daniel Nyström wrote:

> > Daniel Nyström wrote:
> > >
> > >And another question at the same time; what's really E1?
>
> > >How is E1 devices connected? Seems like regular Cat5 cables, but it
> > >problably ian't?
>
> > >If anyone's using Adit 600, did they send all cables required for
> > >connecting to the FXS channels? Seems like a very unique "plug" on
> > >the side of Adit.

E1 is a serial interface with one of a few line encodings. Sometimes 
(often) a channel structrure is applied which leaves 31 channels of 
64 kb/s each. Other protocols can then be applied on top of the E1 such as 
isdn etc.

E1 is (almost) always deliverd as either an RJ45 plug with balanced 
120 ohm impedance (most common) or as two coaxial cables with unbalanced 
75 ohm impedance (uncommon). Other weird and wonderful connectors are 
sometimes used by specific equipment such as routers. For the rj45 case a 
normal cat5 cable will do. E1 uses the pairs 3-6 and 4-5. A cat5 cable 
normally has the pairs 1-2, 3-6, 4-5 and 7-8 of which ethernet uses 1-2 
and 3-6.

I have not looked at the Adit but I suspect they use the standard Amphenol 
connector that is very common in the telecom business. You can get a rj45 
socket list with an amphenol connector on the back, or you can get a 
suitable pig-tail cable and punch it down into a punch-down block for 
furhter wireing.

Peter