Nokia N72 Service Manual page 168

RM-180
Nokia Customer Care BB Troubleshooting and Tuning Guide
Measurement data
Figure 54 Single-ended output waveform of the Ext_in_HP_out measurement when earpiece is connected.
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 55 Differential output waveform of the Ext_in_IHF_out out loop measurement when speaker is connected.
Page 6 –60 COMPANY CONFIDENTIAL Issue 1
Copyright © 2006 Nokia. All rights reserved.