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Tests
Channel Tests
4-14
SpectraComm 553 Fractional T1 DSU
076R155-000
Installation and Operation Manual
Issue 7
Figure 4-16
Channel Remote Digital Loop with Self Test
553
OOF NS
INS
ON
L
I
N
E
I
N
O
U
T
RSP
SD
RD
EQ
BPV
AIS
TM
ALM
CH
T1
RL
TX
RX
M
O
N
SC 553 DSU
Remote DSU
TPG
TPC
Framer
TX
Driver
Analog
Receiver
Network
Analog
Receiver
TX
Driver
Framer
TPG = Test Pattern Generator
TPC = Test Pattern Checker
DTE
Inter-
face
DTE
Inter-
face
2. TM indicator On during test. Blinks to indicate a detected error.
Lit steadily while pattern is received correctly.
1. To start the test from the front panel, press RL and hold for
2 seconds. RL indicator is lit during the test.
Press switch again to end the test.