Fm Radio Troubleshooting; Audio Troubleshooting; Audio Troubleshooting Test Instructions - Nokia n81 Service Manual

RM-179; RM-223
Baseband Troubleshooting

FM radio troubleshooting

Troubleshooting flow

Audio troubleshooting

Audio troubleshooting test instructions

Single ended external earpiece and differential internal earpiece/IHF outputs can be measured either with a
single ended or a differential probe.
When measuring single ended, each output is measured against ground.
Note: Do not connect ground of single ended probe to 2nd signal of differential lines.
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, input signal
frequency must be set to 2kHz.
The signal for input is single ended.
Required equipment
The following equipment is needed for the tests:
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