User's Manual

B-4
Relay Station RS422 Pin-outs
The R/F Relay Stations are connected by twisted pair wire -- use Belden
1227A1, Cat 5 wire, or equivalent. The Relay Port on the Base Station
and the Relay Port on the Relay Station are connected with a straight cable
using the following pin-outs:
Base Connector Pin # Relay Connector
Receive Data + 5 Transmit Data +
Receive Data - 6 Transmit Data -
Transmit Data + 2 Receive Data +
Transmit Data - 3 Receive Data -
Make a cable with 5-5, 6-6, 2-2, and 3-3 (a straight cable); but, be careful
that you select wires so that the 2 wire is in the twisted pair with the 3
wire, and the 5 wire is in the twisted pair with the 6 wire.
For all RJ Cable pin numbers, number from left to right with the metal pin
side of the connector facing you and the cable running to the down position
Relay Test Plan and Failures
Relay Failure
Relay Station failures are often cable-related. If a Terminal puts out a “Who
Can Hear Me?” message and a Relay that is for some reason not connected
to the Base Station (bad cable, cut cable, broken connectors) hears it, it
answers with the message:
Relay n Cannot Be
Heard by the Base
Notify Supervisor
Press Any Key
At this point, it is up to the operator to notify someone that the Relay is not
communicating with the Base and to check the cabling first. There is no
message sent to the host, so it is very important that the operator that
receives this message notify someone immediately.
Because relay cabling is often troublesome, we supply a test cable for
isolating the user-made cable from the process. This test cable is so short
that it doesn’t follow the rules of twists on the previous page – it is just a
Ethernet patch cable for node, but adequate for testing the relay.
HINT: Use the suggested wire type, and if you’re doing your own crimping,
be sure to use the expensive metal crimpers ($100) and not the cheap plastic