Samsung SCH-A205 service manual.pdf

DUAL MODE(CDMA/AMPS)

PORTABLE TELEPHONE

SCH-A205

SERVICE Manual

DUAL MODE TELEPHONE

CONTENTS

1. General Instruction

2. Specification

3. Circuit Description

4. NAM Programming

5. Test Procedure & Test Command

6. Electrical Parts List

7. Block Diagram

8. PCB Diagram

9. Schematic Diagrams

10. Exploded View & Its Part List

ELECTRONICS

Samsung Electronics Co.,Ltd. Dec. 99

Pinted in Korea.

Code No.: GH68-02022A

1. General Instruction

The SCH-A205 cellular phone functions as both analog cellular phone working in AMPS(Advanced

Mobile Phone Service) mode and Digital cellular phone working in CDMA(Code Division Multiple

Access) mode.

CDMA type digital mode applies DSSS(Direct Sequential Spread Spectrum) mode which first came

to be used in the military.

The DSSS reduces channel cross talk and allow to use one frequency channel by multiple users in

the same specific area, resulting in increase of channel capacity to about ten times compared to that

of analog mode currently used.

Soft/Sofer Handoff, Hard Handoff, and Dynamic RF Power Control technologies are combined into

this phone to reduce the call drop while usage.

CDMA digital cellular network consists of MSO(Mobile Switching Office), BSC(Base Station

Controller), BTS (Base Station Transmission System), and MS(Mobile Station). MS meets the specifi-

cations of the below :

¤ IS-95A : Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread

Spectrum Cellular System

¤ IS-96A : Speech Service Option 1 Standard for Dual-Mode Wideband Spread Spectrum Cellular

System

¤ IS-98A : Standards for Dual-Mode Wideband Spread Spectrum Cellular Mobile System

¤ IS-126 : Mobile Station Loopback Service Options Standard

SCH-A205 is composed of main handset, one battery(800mAh), ear-microphone, and rapid DTC.

Travel adaptor(or travel charger) and HFK is optional. Hands-Free Kit is designed to be operated in

full-duplex mode taking turn-around delay between the phone and the system into account.

SAMSUNG Proprietary - Contents may change without notice

1-1

2. Specification

2-1 General

ITEM

CDMA

AMPS

Tx Freq. range

824 ~ 849MHz

Rx Freq. range

869 ~ 894MHz

Channel Bandwidth

1.23MHz

30KHz

Channel Spacing

30KHz

Number of Channel

832

Duplex Separation

45MHz

Type of Emission

40K0F8W,40K0F1D

In/Output Impedance

50ohm

Tx Intermediate Freq.

130.38MHz

Rx Intermediate Freq.

85.38MHz

Tx Local Freq.

1st(260.76MHz)

2nd(FTX+130.38MHz)

1st(260.76MHz)

2nd(F TX +130.38MHz)

Rx Local Freq

1st(FRX+85.38MHz)

2nd(170.76MHz)

1st(F RX +85.38MHz)

2nd(170.76MHz)

TCXO freq.

19.68MHz

Freq. Stability

(F RX -45MHz) ±300Hz

±2.5ppm

Operating Temperature

-30°C ~ +60°C

Supply Voltage

3.75V

Size and Weight

STD : 80mm X 43mm X 25.5mm, 85 g, 800 mA

SAMSUNG Proprietary - Contents may change without notice

2-1

2-2 Digital Mode

Waveform Quality

0.944 or more

Time Reference

±1uS or less

Rx Sensitivity and Dynamic Range

-104dBm, FER=0.5% or less

-25dBm, FER=0.5% or less

Maximum TX Output Power

23dBm(200mW)

TX Frequency Deviation

±300Hz or less

Occupied Band Width

1.32MHz

TX Conducted Spurious Emission

900KHz : -42dBc / 30KHz below

1.98MHz: -54dBc / 30KHz below

Minimum TX Power Control

below -50dBm

Open Loop Power Control

-25dBm: -57.0dBm ~ -38.5dBm

-65dBm: -17.5dBm ~ + 1.5dBm

-104dBm: +18.0dBm ~ +30.0dBm

Standby Output Power

below -61dBm

Colsed Loop TX Power Control Range

Test1: ±24dB or less

Test2: 0mS ~ 2.5mS

Test3: ±24dB or more

Test4: ±24dB or more

Test5: ±24dB or more

SAMSUNG Proprietary - Contents may change without notice

2-2

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika: