Check Crystal Circuit - LG KG110 Service Manual

4. TROUBLE SHOOTING

4.2.1 Check Crystal Circuit

R420
AFC
YES
26MHz ok?
NO
Change Y400
26MHz signal
Graph 4-1
Crystal pin1
Graph 4-2
AD6548
9
VLDO3
10
TXOP_LO
11
TXOP_HI
12
VCC_TXVCO
13
VDD
14
VBAT
15
VLDO1
16
VLDO2
1K
C439
0.1u
Y 400
DSX321SL2
VCTCXO Circuit is OK
See next Page to Check
ANT SW & Mobile SW
33
GND
32
RX850
31
RX850B
30
RX900
29
RX900B
28
RX1800
27
RX1800B
26
RX1900
25
RX1900B
C437 1000p
30
Figure 4-3
26MHZ
C438 L409
47p
680nH