LG C3400 Service Manual page 54

(4) Checking SAW Filter Circuit
TEST POINT
FL401
Figure 4-6
Checking Flow
Check RF Level of
Saw Filter Input
For GSM : FL401.3
For DCS : FL402.3
Saw Filter is OK
See next Page to check
Rx IQ Signal
For the test,
RX Stand alone Mode is
needed. Refer to chapter 11
FL402
EFCH942MTCA7
EFCH1842TCA7
No
FL401.3: ~ -64dBm
FL402.3: ~ -64dBm
Check the parts are well
Yes
Soldered
For GSM : L501,C513,C518
For DCS : L503, C521,C522
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CIRCUIT
2 3
G1 O1
1
IN
FL401
G2 O2
5 4
2 3
G1 O1
1
IN
FL402
G2 O2
5 4
Soldering is
OK?
No
Changing
L501,C513,C518 for GSM
L503, C521,C522 for DCS
4. Troubleshooting
C513
1p
L501
27nH
C518
1p
C521
1p
L503
6.8nH
C522
1p
Changing FL401
Yes
for GSM, FL402
for DCS