Nokia RM-627 Service Manual page 83

RM-627
BB Troubleshooting and Manual Tuning Guide
If a special low-pass filter designed for measuring digital amplifiers is unavailable, the measurement must be performed with a
current probe and the input signal frequency must be 2kHz.
Figure 13 Differential output waveform of the Ext_in_IHF_out out loop measurement when speaker is connected.
Figure 14 Single-ended output waveform of the HP_in_Ext_out loop when microphone is connected.
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