User's Manual

Lucent Technologies — Proprietary
See notice on first page
22-54
401-660-100 Issue 11 August 2000
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PK/PCB style circuit board mounted fuses on the AYG3 circuit pack. On
recently manufactured LACs these fuses can be accessed through a cover
plate on the left side of the Linearizer. These fuses can only be checked
with an ohmmeter.
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Before checking any Linearizer fuses, inhibit call processing and turn off all
radios on the LAC. Open the 30 amp LAC circuit breaker which feeds the
Linearizer.
Linearizer Faceplate Fuses 0
Beginning with the 1C LAC, an extra fuse (marked "FCA") was moved from the
inside of the AYG3 circuit pack to the front panel of the Linearizer, allowing it to be
changed in the field.
The position of the fuses and their labels on the front panel of the Linearizer are
shown below, followed by a description of their functions.
FCA
- Protects the Final Correction Amplifier in the Linearizer. This fuse may be
blown if the LAC is overdriven. This fuse is only accessible on C-Series LACs.
Linearizer Fan
- Protects the fan in the Linearizer. This fuse may blow if the fan
fails or if it becomes blocked.
Pre-Amplifier
- There are 2 preamplifier fuses, one for each of the two redundant
RF power paths in the preamp. These fuses may blow if a preamp fails or there is
a short in the preamp power cable. If one of these fuses fails, they should both be
replaced.
Linear Amplifier Unit fan
- Protects the fan in the Linear Amplifier Unit. This fuse
may blow if the fan fails or if it becomes blocked.
AYG3 Circuit Pack Fuses 0
On newly built LACs, there is a cover plate on the left side of the Linearizer sheet
metal which allows access to a row of socketed fuses on the AYG3 circuit pack.
C-Series LACs A/B-Series LACs
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FCA
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Linearizer Fan
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Linearizer Fan
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Pre-amplifier
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Pre-amplifier
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Pre-amplifier
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Pre-amplifier
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Linear Amplifier Unit Fan
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Linear Amplifier Unit Fan