Audio Troubleshooting - Nokia 2255 Baseband Description And Troubleshooting

Nokia Customer Care

Audio Troubleshooting

When troubleshooting the audio, make these common checks (see
• Perform visual inspection of all the ASIPs and the UEMC.
• Inject 1KHz signal into MiC1 and trace it to the earpiece. Only when using IHF
DC block caps
MIC3
UEMC
SIDE
DC block caps
• Make sure the audio amplifier and solder are ok
• Make sure the IHF speaker contacts are ok
• Make sure output is amplified by 5x. If not, check that the gain resistors network
ISSUE 1 10/2005
signal will it be amplified by a factor of 5x.
Audio ASIPs
Audio ASIPs
Figure 10: UEMC Side of Audio Diagram
is correct
©2005 Nokia Corporation
Baseband Description and Troubleshooting
MIC2
Audio amplifier 5X
Company Confidential
2255 (RM-97)
Figure 10):
UHJ
IHF
MIC1
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