LGE Internal Use Only
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. TROUBLE SHOOTING
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RX Trouble
(1) Checking VCTCXO Circuit
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
NX3225SA
X101
26MHz
TEST POINT
CIRCUIT
Waveform
TP1
TP2
Waveform
CHECKING FLOW
TP1
TP2