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Tests
T1 Tests
4-12
SpectraComm 553 Fractional T1 DSU
076R155-000
Installation and Operation Manual
Issue 7
Figure 4-13
T1 Local Test, Network Interface
Figure 4-14
T1 Local Test, Cascade Interface
SC 553 DSU
DTE
Inter-
face
Framer
TX
Driver
Analog
Receiver
Network
HELLO
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
3. Enter test data at the DTE. Compare data entered at the DTE with data
looped back and displayed by the DTE. (Test equipment connected to the
Line jacks can be used in place of the DTE.)
2. TM indicator On while Local Test loopback is active.
1. To start test from front panel, press T1 momentary action switch.
T1 indicator is lit during the test.
Press switch again to end the test.
TX
Driver
Analog
Receiver
Framer
DTE
Interface
Framer
TX
Driver
Analog
Receiver
SC 553 DSU
Network Interface
Cascade Interface
Remote
Device
Network