LG KP175 - Page 46

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4. TROUBLE SHOOTING
(1) Checking Crystal Circuit
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Only for training and service purposes
R706
X500
26 MHzO.K?
No
Crystal Circuit is OK
See next Page to check
Mobile
SW
Yes
Change X500
TEST POINT
WAVEFORM
CIRCUIT
CHECKING FLOW
Graph 4.2.1(a) Graph 4.2.1(b)
0R706
R514
10K
0.1u
C512
2V75_VVCXO
VCC_REF
VAFC_NC
18
VCC_BBQ
24 17 23
Q
QB
22
REFIN
20 19
REFINB
21
REF_OP
C513
0.1u
AFC