LG -600 Service Manual page 35

YES
TX VCO
U208 pin 10
Frequency & Power check
Frequency = 1747.8MHz &
Power >= -15dBm
YES
Power AMP
U100 pin 3
Frequency & Power check
Frequency = 1747.8MHz &
Power >= 18dBm
YES
ANT switch
U203 pin 2
Frequency & Power check
Frequency = 1747.8MHz &
Power >= 15dBm
YES
✔ RF Connector U107 soldering
check
✔ RF Connector chip check
✔ Matching network L101, L105,
C108 soldering check
YES
END
✔ U208 soldering check
✔ U208 pin 5 DC 2.8V check
✔ U208 pin 3 control signal check
NO
( >= 1Vp-p )
✔ U208 4 Low Voltage check
✔ U208 7 High Voltage check
✔ U208 change another same one
✔ U100, U101 soldering check
✔ U100 pin 4 VBAT DC Voltage
NO
check ( > 3.3V )
✔ U101 pin 1 DC Voltage check
( > 3.3V)
✔ U101 pin 3 TXON HIGH Voltage
check
✔ U101 pin 4 BSW HIGH Voltage
check
✔ U101 pin 8 Vapc signal check
✔ U101 pin 2 1747.8MHz freq &
power check
✔ U102 coupler input, output
Freq & Power check
✔ U100, U101,102 change
another same one
NO
✔ U103 soldering check
✔ U103 pin 4 LOW Voltage check
✔ U103 pin 14 HIGH Voltage check
✔ U103 pin 11 LOW Voltage check
✔ U103 change another same one
REMARKS
1. Call connection : TEM3 execution
ti
tms1
txpw 1 102 Enter
rfpw 1 700
rfpw 1 700
rfe 7
2. Spectrum analyzer : SPAN = 1MHz
VBW = 1MHz
RBW = 3MHz
Press the trace button of spectrum analyzer on checking
test and press the max hold of spectrum analyzer
3. Oscilloscope : 500mV/div , 2ms/div
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5. Data Kit & Test Method
Enter
Enter
Enter
Enter
Enter