Service Diagrams; Introduction; Test Point Measurements - Motorola A920 Service Manual

Introduction

The service diagrams were carefully prepared to allow
a Motorola certified technician to easily troubleshoot
cellular phone failures. Our professional staff provided
directional labels, color coded traces, measurement val-
ues and other guidelines to help a technician trouble-
shoot a cellular phone with speed and accuracy.
We worked hard in trying to provide the best service
diagrams, therefore, to avoid cluttered diagrams, we
may exclude some components from the service dia-
grams. Our professional staff carefully selected to ex-
cluded components that are unlikely to fail.

Test Point Measurements

The measurements labeled on the service diagrams are
approximate values and may vary slightly. These mea-
surements are dependent on the accuracy of the test
equipment.
It is strongly recommended that the test equipment cali-
bration schedule be followed as stated by the manufac-
turer. RF probes should be calibrated for each frequency
in which tests are going to be performed.
The types of probes used will also affect measurement
values. Test probes and cables should be tested for RF
losses and loose connections.
Preliminary
Because of the sensitivity of RF, measured readings will
be greatly affected if they're taken in certain locations.
To get the most accurate readings, take measurements
nearest to the labeled measurement on the service dia-
gram.
Motorola Confidential Proprietary
Service
Diagrams
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