Camera Hardware Troubleshooting; Audio Troubleshooting; Audio Troubleshooting Test Instructions - Nokia RM-721 Service Manual

RM-721; RM-722
BB Troubleshooting and Manual Tuning Guide

Camera hardware troubleshooting

Troubleshooting flow

Audio troubleshooting

Audio troubleshooting test instructions

Single-endedl external earpiece and differential internal earpiece outputs can be measured either with a
single-ended or a differential probe.
When measuring with a single-ended probe each output is measured against the ground.
Internal handsfree output is measured using a current probe, if a special low-pass filter designed for
measuring a digital amplifier is not available. Note also that when using a current probe, the input signal
frequency must be set to 2kHz.
The input signal for each loop test can be either single-ended or differential.
Required equipment
The following equipment is needed for the tests:
• Oscilloscope
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