LG H990ds - GSM DRx Signal Path (Bands 850;900)

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reserved. Only training and service purposes
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3. TROUBLE SHOOTING
Checking DRX RF signal path (GSM 850/900 )
3.7.3 GSM PART – GSM 850/900 DRx
Checking Flow Image
Check TP1
Signal exist?
START
Check SW1100 Soldering
YES
NO
Check TP2
Signal exist?
YES
Check FL1200 Soldering
NO
Check TP3
Signal exist?
YES
Check U1202 Soldering
NO
Check TP4/5
Signal exist?
Check U1204 Soldering
NO
Check next step
Check Transceiver
physical damage or soldering
condition
OK
Replace U1401
NOT GOOD
YES
BOTTOM
TP1
(DRx Common)
SW1100
U1202
U1204
TP2
(GSM850/900 DRx )
TP3
(GSM850/900 DRx )
FL1200
TP4
(GSM850 DRx )
TP5
(GSM900 DRx )
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