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LGE Internal Use Only
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
6. Trouble shooting
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6.13.1 FEM Circuit
√
Part Description of FEM
√
Check point of FEM
Application Mode
VC1
VC2
EGSM
Tx High
Low
Rx
Low Low
DCS1800
Tx Low
High
PCS1900
Rx Low
Low
FEM Circuit
Check the next part
Check
Control signal of
FEM(TP1&TP2)
Replace
PCB
NO
YES
R500
R591
U501
Fig 10 Debugging flowchart of FEM circuit
Fig 11 FEM circuit (U501)
33p
C500
NA
L585
1
R501
15
GSM1800_1900_TX
7
GSM1900RX_OUT1
GSM1900RX_OUT2
8
GSM850RX_OUT1
1
GSM850RX_OUT2
2
17
GSM850_900_TX
3
GSM900RX_OUT1
GSM900RX_OUT2
4
21
NC
19
VC1
VC2
20
LSHS-C085FB
U501
11
ANT
GND1
9
24
GND10
GND2
10
12
GND3
GND4
13
GND5
14
GND6
16
18
GND7
22
GND8
23
GND9
GSM1800RX_OUT1
5
GSM1800RX_OUT2
6
1
R500
VC2
VC1
Control Signal of FEM
TP1
TP2
Содержание KC550
Страница 1: ...Date May 2008 Issue 1 0 Service Manual Model KC550 Service Manual KC550 Internal Use Only ...
Страница 129: ... 130 LGE Internal Use Only Copyright 2008 LG Electronics Inc All right reserved Only for training and service purposes ...
Страница 155: ...LGE Internal Use Only Copyright 2008 LG Electronics Inc All right reserved Only for training and service purposes 156 ...
Страница 182: ...Note ...
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