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1. General Description
The SCH-620 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/Softer 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 specifications 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 Systems
•
IS-98A : Standards for Dual-Mode Wideband Spread Spectrum Cellular Mobile Station
•
IS-126 : Mobile Station Loopback Service Options Standard
SCH-620 is composed of main handset, rapid charger, three batteries (1600 mAh, 1000 mAh, 550mAh), hands-
free kit, car adaptor, and travel charger. 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
Summary of Contents for SCH 620
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Page 79: ...PCB diagrams Samsung Electronics 10 2 10 2 Main PCB Bottom Diagram ...
Page 80: ...PCB diagrams Samsung Electronics 10 3 10 3 CLC PCB Top Diagram 10 4 CLC PCB Bottom Diagram ...
Page 81: ...PCB diagrams Samsung Electronics 10 4 10 5 Hands free Kit PCB Top Diagram ...
Page 84: ...Samsung Electronics 11 3 Circuit diagrams 11 3 CLC Circuit Diagram ...
Page 85: ... Samsung Electronics Co Ltd APRIL 2000 Printed in Korea Code No GH68 00669A BASIC ELECTRONICS ...