LG PX8700 Service Manual page 39

PX8700
4.1.1.2 Checking VCTCXO Circuit
Test Point
Waveform
Graph
LG Electronics Inc.
Check X101 Pin 3
◆ Refer to Graph 4.1.1(a)
Check X101 Pin 4
◆ Refer to Graph 4.1.1(b)
X101
Checking Flow (VCTCXO)
YES
19.2MHz
?
No
+2.8V OK?
NO
YES
Changing X101
Check R125, R127
C1002
YES
Similar?
NO
SW Download
Replace Board
Graph
VCTCXO Circuit is OK .See
next Page to check
Control signal
The Problem may
be Logic part
Refer to Logic troubleshoot
VCTCXO Circuit is OK.
See next Page to check
Control signal
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