Specifications

3-12
PA-T3+ Serial Port Adapter Installation and Configuration
OL-3505-03
Chapter 3 Removing and Installing Port Adapters
Connecting a Serial Cable
Connecting a Serial Cable
On a single one-port PA-T3+(=), you can use two 75-ohm coaxial cables (one for the receive port
[RCVR] and one for the transmit [XMTR] port). You can use four 75-ohm coaxial cables on the two-port
PA-2T3+(=). Cisco 75-ohm coaxial cables are available only from Cisco Systems.
Caution You can attach only an EIA/TIA-612 or EIA/TIA-613 serial cable to the PA-T3+ installed in your router.
Attaching a serial coaxial cable of another interface type to the port adapter could damage your router
or the hardware at the network end of the cable.
Each T3 link requires separate receive and transmit connections to your external T3 equipment.
To connect the 75-ohm coaxial cables to the PA-T3+ port adapter, follow these steps:
Step 1 Attach the 75-ohm coaxial cables directly to the BNC ports on the PA-T3+. Attach one end of a cable to
the port labeled XMTR and one end of a second cable to the port labeled RCVR. (See Figure 3-3.)
Note We strongly recommend that you fasten together your transmit and receive cables along their entire
length, as shown in . Doing so reduces the effects of EMI. You can use standard heat-activated shrink
tubing or cable ties for this purpose.
You can also use a 75-ohm coaxial cable pair that is available from Cisco Systems (Product Number
CAB-ATM-DS3/E3[=]).
Figure 3-3 Attaching 75-ohm Coaxial Cables to a PA-T3+
Caution To prevent system problems and to maintain the proper cable connection sequences, connect the receive
and transmit ports on your PA-T3+ as indicated in Step 2.
30289
To TX port
on external
T3 equipment
To RX port
on external
T3 equipment
BNC
cables
RCLK
XMTR
RCVR
ENABLED
FERF
OOF
RL
LL
RCLK
FERF
RL
AIS
OOF
LL
AIS
2DS3+ SERIAL
XMTR
RCVR