SYMPTOM
PROBLEM
SOLUTION
APPENDIX A
TROUBLESHOOTING
LEDs do not light
when AC power
transformer is
plugged into wall
Carrier Detect (CD)
LED is
low
or
Carrier Detect (CD)
LED is
high, but
1180s are not
communicating
Loose power
connection
Outlet is defective
AC power cord is
defective
AC transformer is not
plugged into the Model
1180
If CD is low, possible
synchronization loss
Test Mode switch is in
the wrong position
DIP switches are set
improperly
Fiber link is connected
improperly
RS-232 connections
are faulty or cables are
pinned wrong
Make sure the AC
connection is flush
Try a different outlet
Remove the cord from
the outlet and check for
continuity
Plug transformer into
Model 1180
Check for ongoing
power loss or break in
fiber if CD does not go
high within 60
seconds
Make sure the Test
Mode switch is set to
NORMAL on both
Model 1180s
Check all DIP switch
settings, esp. Reset
and Data Rate,
against Section 3;
make sure both Model
1180s are configured
the same way
Check the ST or SMA
connection on the back
of both Model 1180s
Check RS-232 cable
continuity and pinning
13
SYMPTOM
PROBLEM
SOLUTION
Data passes, but
hardware flow
control doesn’t
work
Model 1180s work
in async. mode,
but not sync. mode
Incorrect DIP switch
setting
Incorrect DIP switch
setting
Switch 7 must be in the
ON condition for
hardware flow control
signals to pass
between Model 1180s;
both units must be set
the same way
Switch 8 (internal/
external clock) must be
set the same way for
both Model 1180s
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