[Asterisk-Users] [OF] Cable Pinouts

[Steve Underwood]

Eduardo Goncalves wrote:

>Hi,
>
>Digium's E400P has RJ45 conector and my E1 link has BNC concetor. Could someone tell me the cable pinouts to make this conection?
>
Your BNC is a 75ohm unbalanced line. The E400P expects a 110ohm balanced 
line. If you are lucky you can just fudge the connections. When the line 
is longer you normally need a little balun gadget to interface them. 
These contain almost nothing, but can cost quite a lot. A cheaper 
solution is to go to a place that sells CCTV for security. They usually 
have cheap BNC to twisted pair adaptors. These are not quite the right 
impedance match for the E1 application, but usually work OK.

The pinout for the RJ48C (it looks and feels like an RJ45, but it is 
really an RJ48C) on the E400P is:

pin 1 receive ring
pin 2 receive tip
pin 3 N/C
pin 4 transmit ring
pin 5 transmit tip
pin 6 N/C
pin 7 frame ground
pin 8 frame ground

Regards,
Steve