Gsm Transmitter - Samsung sgh-a500 Service Manual

SGH-A500 Flow Chart of Troubleshooting and Circuit Diagrams

10. GSM transmitter

YES
OSC202
OSC202
C H E C K /
PIN4=2.8V?
CHANGE
NO
U601
CHECK/
CHANGE
YES
OSC201
OSC201
C H E C K /
PIN7=2.8V?
CHANGE
NO
U601
CHECK/
CHANGE
U201
CHECK/
CHANGE
YES
OSC101
OSC101
C H E C K /
PIN5=2.8V?
CHANGE
NO
U601 CHECK/
CHANGE
CN101 CHECK/
CHANGE
7&19=2.8V?
YES
OSC202
NO NO
PIN3>13MHz PIN25=1.6~
2.5Vrms? 1.8Vpp?
YES
OSC101
YES
dBm(902.4MHz
OSC201
NO
YES
PIN1=(1326.4
MHz)-3~3
dBm?
YES
dBm(902.4MHz
YES
U201
NO
PIN28>-10 PIN10=22~24d
dBm(902.4M Bm(902.4MHz)
Hz)?
YES
YES
OSC101
NO
PIN6>9
PIN5=22~24
dBm(902.4
dBm(902.4MHz)
MHz)?
YES
YES
F105
CHECK/
CHANGE
PIN8=22~24dBm(
902.4MHz)?
YES
CON101
NO
PIN1=22~24
dBm(902.4MHz)
?
YES
ANT1
CHECK/
CHANGE
SAMSUNG Proprietary-Contents may change without notice
U201 NO U601
PIN CHECK/
CHANGE
U201
NO
YES
NO
PIN6>9 OSC101
PIN5=2.8V?
)?
F101
F101
NO
PIN3>8
CHECK/
CHANGE
)?
NO
U103 U103
NO
PIN6&8=
3.4~4.2V
? ?
U601
F103
NO
CHECK/
F103
CHANGE
CHECK/
CHANGE
?
U101
NO NO
U101
PIN2=0~0.5V
&PIN11=2.5~
2.8V?
YES
CHECK/
U104&U105
CHANGE
PIN4=2.8V
?
NO
YES
U104&U105 U601
CHECK/ CHECK/
CHANGE CHANGE
6-8
CONTINUOUS Tx ON
CONDITION
CH : 62
Tx POWER LEVEL : 10
RBW : 300KHz
VBW : 300KHz
ATT. : 30dB
OSC101
CHECK/
CHANGE
U103
BATTERY
CHECK/
CHECK/
CHANGE
CHANGE
U103
YES YES
U103
PIN14=
PIN16=
1.5~1.9V
0~0.5?
?
NO
U201
CHECK/
NO
U102
CHANGE
PIN10=2.8V
?
YES
F104
F103
NO
PIN4>902.4
CHECK/
MHz(-18dB
CHANGE
m)?
YES
NO
U102
F104
U101
PIN5>902.4
CHECK/
MHz(-28dB
CHANGE
m)?
YES
U102
CHECK/
CHANGE
YES
NO