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TC1540D User's Manual
Rev. 1.2
Optic Loopback Bench Test
Purpose:
This test loops the optic signal transmitted by the TC1540 back to the unit's receiver in
order to test the transmit and receive capabilities of the unit without any other units
attached.
Equipment
Requirements:
One (1) Bit Error Rate Test (BERT) Set with appropriate interface module.
One (1) optical jumper cable (patch cord) with appropriate connectors.
Procedure:
Set up the bench test as shown in Figure 15. To test the "Tx" to "Rx" loop, connect an
optic patch cord from optic "Tx" to optic "Rx." Set all the DIP switchs to the Left position.
Connect a BERT tester to the TC1540 according to Fig. 15. Set the tester up as a DTE
device. The BERT tester should indicate a "SYNC" signal.
Remove the patch cord from "Tx" and "Rx", the "O-SYNC" LED on the TC1540 should
flash.
Figure 15. connect TC1540 to RS-530 or RS-449 Devices
Connect TC1540 to RS-530 DTE device
RS-530
DTE DEVICE
(DB25)
TC1540
Tx-
2
Rx-
3
Tx+ 14
Rx+ 16
IN-
OUT-
IN+
OUT+
SIG
GND
SIG
GND
7
TC1540
Optical loopback
Rx
Tx
RS-422
485/232
BERT
or
ASCII Terminal
All the SW to the left
Figure 16. Optic Loopback Bench Test Connection Diagram
Connect TC1540 to RS-449 DTE device
RS-449
DTE DEVICE
(DB37)
TC1540
Tx-
4
Rx-
6
Tx+ 22
Rx+ 24
IN-
OUT-
IN+
OUT+
SIG
GND
SIG
GND
19
