Checking Vtcxo Block - LG KU730 Service Manual

4.3 Checking VTCXO Block

The reference frequency (19.2MHz) from X100 (VCXO) is used WCDMA TX part, GSM part and BB part.
Check 1. Crystal part
If you already check this crystal part, you can skip check 1.
Test Point (Crystal Part)
TP1
TP2
TP1
C161 C162 C163
1000p 1000p 0.1u
TP3
19.2MHz
VCC GND
4
X100
OUT VCONT
3
TG-5001LA-19.2MHz
C181
1000p
Schematic of the Crystal Part
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4. TROUBLE SHOOTING
VREG_TCXO_2.85V
TP2
2
R130
TRK_LO_ADJ
1
100
C172
0.01u
C180 100p
TCXO_PM
TCXO_BT_IN
TP3