Only For Training And Service Purposes - LG KP105 Service Manual

4. TROUBLE SHOOTING
RX Trouble
(1) Checking VCTCXO Circuit
TEST POINT
U401
TP1
CIRCUIT
X101
TP1
4
GND2
1 HOT1
26MHz
LGE Internal Use Only
SW401
FL401
U103
TP1
X101
NX3225SA
HOT2 3
TP2
2
GND1
CHECKING FLOW
Is the waveform
of Pin3 similar to
DCXO(X101)
Waveform?
Yes
DCXO Circuit is OK.
See next page to check
PLL Circuit.
Waveform
Waveform
TP2
TP1
Copyright © 2008 LG Electronics. Inc. All right reserved.
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No
Replace
X101

Only for training and service purposes