1558A APS
2-6
Installation
NOTE: If the 1558A DTE is configured for AMI opera-
tion, the test sets must be set up to generate either a 511,
2047, or 1:7 pattern. If the 1558A is configured for B8ZS
on the DTE and NET sides, any pattern may be used (511,
2047, 1:7, QRSS, 3:24, etc.). When sending a 1:7 pattern,
though, some T1 test sets inherently cause generation of a
yellow alarm condition.
2)
Verify that there is no connection at the NET A jack.
3)
Manually operate the front panel Path Select Switch to
the (A) position. This forces and locks the unit to Path A.
The following unit status LEDs associated with Path A test-
ing should be illuminated on the unit:
• Power A or B LED ON (green)
• Status ‘Locked’ LED ON (yellow)
• Status Path Active ‘A’ ON (green)
• The Path Status, Alarm A (red) LED may be ON or OFF
depending on the alarm timer setting (0 to 900 seconds)
configured in the 1558A.
4)
The 1558A unit is now looped back to the DTE port
and the T1 test set should be running in sync and error free.
If not, verify that the T1 test set framing and line coding set-
ting match the settings configured in the 1558A.
The 1558A unit is now looped back to the DTE port and the
T1 test set should be indicating that it is detecting pattern
sync and running error free. If “yes” proceed to Path B,
Preservice Testing. If “no”, verify that Steps 1 - 4 have been
completed properly. If there is still a problem, perform the
following:
• Loop the T1 test set to itself and verify that test set runs
error free.
• Verify that the T1 test set is properly configured to operate
with the options set in the 1558A (D4 or ESF, AMI or
B8ZS).
• Also verify that the T1 test set is configured to supply
clock (internal).
S1
DTE
COM BUS
NET B
NET A
IN
OUT
S2
S3
S4
Bantam Patch Cord
Path NET A
Figure 2-2
Local 1558A Test Diagram, Path A and Path B
RX BRDG
TX BRDG
N
E
T
A
RX BRDG
TX BRDG
N
E
T
B
RX BRDG
TX BRDG
D
T
E
Bantam Patch Cord
Path NET B
RX BRDG
TX BRDG
N
E
T
A
RX BRDG
TX BRDG
N
E
T
B
RX BRDG
TX BRDG
D
T
E
T1 Test Set Configured for:
Framing - D4 or ESF
Line Code - AMI or B8ZS
Clocking - Internal
Pattern - QRSS, 1:8, 3:24, etc.