General DataComm SpectraComm 800 T3, Руководство по установке и эксплуатации

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Diagnostics Diagnostics Overview
076R160-000 SpectraComm 800 T3 Data Service Unit 4-7
Issue 4 Installation and Operation Manual
Remote Lineloop with Self Test and Remote Payload Loop with Self Test
Remote Line Loop with Self-Test isolates the local DSU from the DTE and checks the DSU internal
circuits, the T3 link, and the remote DSU. The test procedure involves two functions:
• Remote Test causes the local DSU transmits an in-band command to its remote DSU,
directing the remote to loop received signals back onto the network.
• Self-Test causes the DSU enables its internal Test Pattern Generator to provide the signal
for the Remote Loop and enables its Test Pattern Checker to verify the signal. The DSU
is isolated from its DTE while the Test Pattern Generator and Checker are enabled.
Note
Remote loopbacks are for C-Bit Framing only.
Figure 4-8 Remote Line Loop with Self Test
Figure 4-9 Remote Payload Loop with Self Test
MASTER SC800 T3 DSU
Tx DRIVER
ANALOG
RECEIVER
T
3
N
E
T
W
O
R
K
F
R
A
M
E
R
DTE
INTERFACE
REMOTE SC800 T3 DSU
Tx DRIVER
ANALOG
RECEIVER
F
R
A
M
E
R
DTE
INTERFACE
GEN
CHECKER
MASTER SC800 T3 DSU
Tx DRIVER
ANALOG
RECEIVER
T
3
N
E
T
W
O
R
K
F
R
A
M
E
R
DTE
INTERFACE
REMOTE SC800 T3 DSU
Tx DRIVER
ANALOG
RECEIVER
F
R
A
M
E
R
DTE
INTERFACE
GEN
CHECKER