LG KP105 - Page 47

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4. TROUBLE SHOOTING
RX Trouble
(1) Checking VCTCXO Circuit
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U401
SW401
U103
X101
FL401
TP1
TP1
Is the waveform
of Pin3 similar to
DCXO(X101)
Waveform?
Replace
X101
Yes
No
DCXO Circuit is OK.
See next page to check
PLL Circuit.
2
GND1
GND2
4
1
HOT1
HOT2
3
NX3225SAX101
26MHz
TEST POINT
CIRCUIT
Waveform
TP1
TP2
Waveform
CHECKING FLOW
TP1
TP2