CANOGA PERKINS 2240 Fiber Optic Modem User Manual
Page 99
2240 Fiber Optic Modem
99
Step
Symptom
Possible Cause(s)
Action
3
Cable loss exceeds
Defective
Repair or
modem loss budget.
F/O cable
replace defective
cable
4
Cable loss exceeds
Defective Fiber
Repolish or
modem loss budget.
Optic Connectors
replace defective
connector
5
Set the Remote Loopback switch on the near-end modem. Set up BERT
tester for the proper clocking, data rate and format as used with the
circuit. Use the existing interface cables if possible. Connect the BERT
tester in place of the near-end user device. Run the BERT test and go to
the next step.
6
Loopback test passes
Modem not
Verify / correct
but modems will not
configured
switch and strap
pass data.
properly
settings on modem
and devices
7
Loopback test passes
Interface cables
Repair damaged or
but modems will not
damaged or mis-
miswired cables
pass data.
wired.
8
Optically loopback
each modem and repeat
BERT test as detailed in
Step 5 of this procedure.
Modem fails BERT
Defective modem or
Replace defective
test when optically
electrical interface
modem
looped back to itself.
9
Set the Local Loop-
back switch on the
near-end modem.
Modem fails BERT
Defective modem or
Replace defective
when looped locally
electrical interface
modem