Hello Friend!
E1 cables used by AR routers and the line orders of the cables are described as follows: E1 cables include DB9-BNC cables and RJ45-BNC cables. The impedance of the cables can be 75 ohms, 120 ohms, and 100 ohms. Note: You are not advised to make E1 cables by yourself. 1. DB9-BNC cables: (apply to E1 cards with one interface or two interfaces) DB9 pin1---Rx+Signal---BNC1 core wire (Rx) DB9 pin2---Rx-Signal---BNC1 insulated wire (GND) DB9 pin6---Tx+Signal---BNC1 core wire (Tx) DB9 pin7---Tx-Signal---BNC1 insulated wire (GND) 2. RJ45-BNC cables: (apply to E1 cards with four and eight interfaces) RJ45 pin1---Rx-Signal---BNC1 core wire (Rx) RJ45 pin2---Rx+Signal---BNC1 insulated wire (GND) RJ45 pin4---Tx-Signal---BNC1 core wire (Tx) RJ45 pin5---Tx+Signal---BNC1 insulated wire (GND) 3. Pin definition: Assume that a DB9 connector is put in a method that the wider end is at the top, Pin 1 to Pin 9 of the connector are defined in a sequence from left to right and from top to bottom. Assume that an RJ45 connector is laid flat, Pin 1 to Pin 8 of the RJ45 connector are defined in a sequence from left to right when you face to the front of the connector.
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