3-13
PA-MC-2T3+ Multi-Channel T3 Port Adapter Installation and Configuration
OL-3526-05
Chapter 3 Removing and Installing Port Adapters
Cables and Connectors
Cables and Connectors
The interface connectors on the PA-MC-2T3+ are coaxial BNC types, with one connector for transmit
(TX) and one for receive (RX). The BNC connectors are transformer-coupled to the PA-MC-2T3+ line
interface unit (LIU), which is the analog physical interface on the PA-MC-2T3+.
The pinout and signal descriptions for the BNC connectors on the PA-MC-2T3+ are as follows:
•
Transmit (TX)—Transmitted signals appear on the center contact, and the outer shield is grounded
for the 75-ohm 734A coaxial cable you attach to the TX BNC connector.
•
Receive (RX)—Received signals appear on the center contact, and the outer shield is grounded for
the 75-ohm 734A coaxial cable you attach to the RX BNC connector.
Caution
To prevent problems when long cable lengths are required, you
must
ensure that your 75-ohm coaxial
cables meet or exceed 734A specifications. See
“T3 Specifications” section on page 1-3
for supported cable lengths.
shows the typical 75-ohm 734A coaxial cable pair recommended for use with the
PA-MC-2T3+. Use one 75-ohm coaxial cable for each PA-MC-2T3+ connection: RX and TX.
Note
Cisco Systems does not supply cables with the PA-MC-2T3+. You must supply your own cables.
Figure 3-6
75-Ohm 734A Coaxial Cable Pair
Connecting the Cables
This section describes the procedure for attaching 75-ohm, 734A coaxial cables between the
PA-MC-2T3+ port adapter and your external DS3 equipment. To continue your PA-MC-2T3+ port
adapter installation, you must install the port adapter cables. The instructions that follow apply to all
supported platforms.
Connect the 75-ohm coaxial cables to the PA-MC-2T3+ port adapter as follows:
Step 1
Attach the 75-ohm coaxial cables directly to the BNC ports on the PA-MC-2T3+ port adapter. Attach
one end of a cable to the port labeled TX and one end of a second cable to the port labeled RX. (See
To PA-MC-2T3+
Rx (In)
Tx (Out)
Tx
Rx
To DS3 equipment
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