Sidetone Not Transmitted (Mic); Sidetone Not Transmitted (Hands Free Mic ) - Pantech GB210 Service Manual

GB210 Service Manual
6.2.2 Side Tone Not transmitted (Mic.)
1. Check to see if Mic + pin is around 1.8V : CP125
NO Check that R470, R152, C184 and C155 is cold solder, broken, short to the other
PCB pattern or not
If you find out any defective part, you replace it.
Set to HP8922M to connect a call and then set to 1kHz with Echo audio mode.
2. Check U102.MIC101 (C156) pins for wave form : CP126
NO Replace MIC
6.2.3 Side Tone Not transmitted ( Hands-free Mic. )
Repeat 6-2-2 No receiving tone heard.( Hands-free Earphone ).
1. Check to see if U102. P15 (C161) pin is around 1.5V : CP127
NO Check that B101, R155, R153 and U112 is cold solder, broken, short to the other
PCB pattern or not.
If you find out any defective part, you replace it.
Set to HP8922M to connect a call and then set to 1kHz with Echo audio mode.
2. Check U102. P15 (B101) pins for wave form : CP127
NO Replace Handsfree Mic
33
PANTECH
CP125
CP126
R&D CONFIDENTIAL
CP127