Toshiba CTX28 manual Test Rdtu Lines

T1

Loop Back Testing

Refer to Figure 8-3and the CSU manufacturer’s Installation and Maintenance manual for information on CSU Local/Network Loopback Tests.

RDTU	RDTU Amphenol Pin Nos.
RDTU TX Open
	NDTU Cable
MITEL Chip
	P1/P26 Transmit
P4	CSU
	P2/P27 Receive
MM8976B

Network

Interface

Unit (NIU)

Network

2581

Top LED

T1

	LEDS ON RDTU PCB
0	Busy	ON Steady
0	FALM	ON	OFF	OFF	OFF	ON	Continue to Cycle when
0	FMALM	OFF	ON	OFF	OFF	OFF	P4 is in ON Position
0	YALM	OFF	OFF	ON	OFF	OFF
0	BALM	OFF	OFF	OFF	ON	OFF

Bottom LED

	T1	T2	T3	T4	T5	T6 T = About 1/2 Second
0	Primary SYNC	ON or OFF, Steady
0	Secondary SYNC	ON or OFF, Steady

1673

Figure 8-12 Network/CSU/RDTU Span Test

Notes

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Local loop back and network loop back test cannot be performed simultaneously.

CSU local/network loop back is a function of the CSU, not all CSUs provide this function – see CSU I&M documentation for CSU loop back test procedures.

Test RDTU Lines

After loop back testing is complete and synchronized with the far end T1 circuit, perform test calls on all RDTU lines.

Strata CTX I&M 06/04 8-21