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GSM TELEPHONE
SGH-C240
GSM TELEPHONE CONTENTS
1. Safety Precautions
2. Specification
3. Product Function
4. Array course control
5. Exploded View and Parts List
6. MAIN Electrical Parts List
7. Block Diagrams
8. PCB Diagrams
9. Flow Chart of Troubleshooting
10. Reference data
CONTENTS
1. Safety Precautions
1-1. Repair Precaution......................................................................................................1-1
1-2. ESD(Electrostatically Sensitive Devices) Precaution...............................................1-2
2. Specification
2-1. GSM General Specification.......................................................................................2-1
2-2. GSM Tx Power Class...............................................................................................2-2
3. Product Function
4. Array course control
4-1. Software Adjustments................................................................................................4-1
4-2. Software Downloading...............................................................................................4-2
5. Exploded View/Disassembly & Assembly Instructions
5-1. Cellular phone Exploded View..................................................................................5-1
5-2. Cellular phone Part list.............................................................................................5-2
5-3. Disassembly & Assembly Instructions......................................................................5-4
6. MAIN Electrical Parts List
7. Block Diagrams
8. PCB Diagrams
CONTENTS
9. Flow Chart of Troubleshooting
9-1. Baseband
9-1-1. Power On................................................................................................................9-1
9-1-2. Initial........................................................................................................................9-3
9-1-3. Sim Part..................................................................................................................9-5
9-1-4. Microphone Part......................................................................................................9-7
9-1-5. Speaker Part...........................................................................................................9-9
9-1-6. LCD Backlight.......................................................................................................9-11
9-2. RF
9-2-1. GSM RX................................................................................................................9-12
9-2-2. DCS RX................................................................................................................9-14
9-2-3. GSM TX................................................................................................................9-17
9-2-4. DCS Tx.................................................................................................................9-19
10. Reference data
1. Safety Precautions
1-1. Repair Precaution
Repair in Shield Box, during detailed tuning.
Take specially care of tuning or test,
because specipicty of cellular phone is sensitive for surrounding interference(RF noise).
Be careful to use a kind of magnetic object or tool,
because performance of parts is damaged by the influence of manetic force.
Surely use a standard screwdriver when you disassemble this product,
otherwise screw will be worn away.
Use a thicken twisted wire when you measure level.
A thicken twisted wire has low resistance, therefore error of measurement is few.
Repair after separate Test Pack and Set because for short danger (for example an
overcurrent and furious flames of parts etc) when you repair board in condition of
connecting Test Pack and tuning on.
Take specially care of soldering, because Land of PCB is small and weak in heat.
Surely tune on/off while using AC power plug, because a repair of battery charger is
dangerous when tuning ON/OFF PBA and Connector after disassembing charger.
Don't use as you pleases after change other material than replacement registered on SEC
System. Otherwise engineer in charge isn't charged with problem that you don't keep this
rules.
1-1
SAMSUNG Proprietary-Contents may change without notice
This Document can not be used without Samsung's authorization
Safety Precautions
1-2. ESD(Electrostatically Sensitive Devices) Precaution
Several semiconductor may be damaged easilly by static electricity. Such parts are called by
ESD(Electrostatically Sensitive Devices), for example IC,BGA chip etc. Read Precaution below.
You can prevent from ESD damage by static electricity.
Remove static electricity remained your body before you touch semiconductor or parts with
semiconductor. There are ways that you touch an earthed place or wear static electricity
prevention string on wrist.
Use earthed soldering steel when you connect or disconnect ESD.
Use soldering removing tool to break static electricity. , otherwise ESD will be damaged by
static electricity.
Don't unpack until you set up ESD on product. Because most of ESD are packed by box
and aluminum plate to have conductive power,they are prevented from static electricity.
You must maintain electric contact between ESD and place due to be set up until ESD is
connected completely to the proper place or a circuit board.
1-2
SAMSUNG Proprietary-Contents may change without notice
This Document can not be used without Samsung's authorization
2. Specification
2-1. GSM General Specification
G SM 90 0 EG SM 900 DCS1800
Ph ase 1 Phase 2 Phase 1
Fr eq. Band [MHz] 8 90~915 880~ 915 1710 ~1785
Up link/ Do wnl ink 9 35~960 925~ 960 1805 ~1880
ARFCN ran ge 1~124 0~124 & 975 ~1023 512 ~885
Tx/Rx spacin g 45MHz 45MHz 95 MHz
Mod . Bit r ate/ 270 .833kb ps 270. 833kbps 270. 833kbps
Bi t Peri od 3 .692u s 3.6 92us 3. 692us
Time Slot Per iod /Fr ame 5 76.9u s 576. 9us 576 .9us
Per iod 4. 615ms 4.615 ms 4.61 5ms
Mo dulat ion 0 .3G M SK 0.3 GMSK 0. 3GMSK
MS Power 33d Bm~13d Bm 33dBm~5dBm 30dBm~0dBm
Po wer Class 5pcl ~ 15pcl 5pcl ~ 19pcl 0pcl ~ 15pcl
Sen sitivity -10 2dBm - 102dBm - 100d Bm
TDMA M ux 8 8 8
Cell Radius 35Km 35 Km 2 Km
2-1
Speclflcation
2-2. GSM Tx Power Class
TX Power TX Power
GSM900 DCS1800
control level control level
5 33