LG P7200 - Page 65

(1) Checking VCTCXO Circuit
4. TROUBLE SHOOTING
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Check Pin 3.
Refer to Graph 4-1(b)
13 MHzO.K?
No
No
VCTCXO Circuit is OK
See next Page to check
ANT SW & Mobile SW
VCTCXO Circuit is OK
See next Page to check
ANT SW & Mobile SW
Yes
Check Pin 4.
Refer to Graph 4-1(a)
2.75V OK?
No
Yes
Changing X601
Check U101
2V75_VVCXO
13MHz
X601
2
GND
3
OUT
VCC
4
VCONT
1
1000p
C604
2.2u
C605
C606
100p
R606
12K
AFC
TEST POINT
CIRCUIT
Waveform
Checking Flow
Graph 4-1(a)
Graph 4-1(b)