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GSM TELEPHONE
SGH-C250




GSM TELEPHONE CONTENTS


1. Specification

2. Exploded View and Parts list

3. Chart of Troubleshooting

4. Array course control

5. Block Diagrams

6. PCB Diagrams

7. MAIN Electrical Parts List

8. Reference data

9. Safety Precautions

10. Product Function
Contents


1. Specification
1-1. GSM General Specification .......................................................................................1-1
1-2. GSM TX power class ...............................................................................................1-2


2. Exploded View and Parts list
2-1. Cellular phone Exploded View ..................................................................................2-1
2-2. Cellular phone Parts list ............................................................................................2-2
2-3. Disassembly ...............................................................................................................2-9
2-4. Assembly ..................................................................................................................2-11


3. Chart of Troubleshooting
3-1. Baseband ............................................................................................................3-1
3-1-1. Power ON .....................................................................................................3-1
3-1-2. System Initial ................................................................................................3-5
3-1-3. SIM Part .......................................................................................................3-8
3-1-4. Charging Part .............................................................................................3-10
3-1-5. Microphone Part .........................................................................................3-12
3-1-6. Speaker Part ..............................................................................................3-15
3-1-7. Camera Part ..............................................................................................3-18
3-1-8. LCD .............................................................................................................3-21
3-2. RF ......................................................................................................................3-13
3-2-1. EGSM Rx ...................................................................................................3-23
3-2-2. DCS Rx ......................................................................................................3-24
3-2-3. PCS Rx ......................................................................................................3-25
3-2-4. EGSM Tx ...................................................................................................3-27
3-2-4. DCS & PCS Tx .........................................................................................3-28
3-2-6. BLUETOOTH ..............................................................................................3-30
Contents

4. Array course control
4-1. Downloading Binary Files ......................................................................................4-2
4-2. Pre-requsite for Downloading ................................................................................4-2
4-3. S/W Downloader Program .....................................................................................4-3


5. Block Diagrams

6. PCB Diagrams

7. MAIN Electrical Parts List

8. Reference data
8-1. Reference Abbreviate ..............................................................................................8-1


9. Safety Precautions
9-1. Repair Precaution ......................................................................................................9-1
9-2. ESD(Electrostaically Sensitive Devices) Precaution ................................................9-2


10. Product Function
1. Specification

1-1. GSM General Specification

EGSM 900 DCS1800
Phase 2 Phase 1

Fr eq. Band[ MHz] 880~91 5 1710~ 1785
Uplink/Downlink 925~96 0 1805~ 1880


ARFCN rang e 0 ~124 & 975~1 023 512~ 885


Tx/ Rx spacing 45 M Hz 95 MHz

Mod. Bit rat e/ 2 70.83 3 kbps 270. 833 kbps
Bi t Pe rio d 3.692 us 3.6 92 us


T ime Slot Per iod/ Fra me 576.9 us 576. 9 us
Period 4. 615 ms 4.615 ms


Modu lation 0.3 G MSK 0.3 GMSK


M S Power 3 3 dBm ~5 dBm 30 dBm ~0 dBm

Power Cl ass 5 pcl ~ 19 pcl 0 pcl ~ 15 pcl

Sensitivity -1 02 dBm - 100 dBm

T DM A M u x 8 8

Cell Ra dius 35 Km 2 Km




1-1
Speclflcation




1-2. GSM Tx Power Class


TX Power TX Power
GSM900 DCS1800
control level control level


5 33