The product must be repaired by the experienced engineers, we will not responsible for the
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1 General
1.1 The purpose of the manual
The manual is just used for the experienced engineer not the general publication, providing
basic reference for electric and mechanic repairing.
1.2 General safety notice
Products with power should be repaired by the experienced engineer any other
person use this manual to repair product may
cause damage to it. Products have many
capacitors with polarity, which should not
be short and in reverse connected. For fear
damage the ESD sensitive components, Pay
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attention to ESD protection during
repairing. Don’t use mobile phone on the
airplane. Don’t use mobile phone near
flammable gas or oil.
2 Summarize
ROCK mobile phone for Russia support Tri-band , the mobile phone can automati c switch in
GSM900 network and DCS1800 、PCS1900 network. Inter antenna reduce the radiation to body
and more easy to take as well as providing good signal. And it has fashionable 65K d ouble color
screen 、inter antenna 、1.3M inter camera 、MP3 、MP4、MMS and GPRS high speed data
transfer、 Bluetooth、FM radio 、color motive game etc functions. There are several difference
between selling in Chinese and Russia. For the detail product feature, please see the Product
Feature document.
3 Identity and safety
Each ROCK mobile phone has one identification number IMEI.
IMEI(international mobile station equipment identities) number is saved in the mobile
memory. One IMEI number exclusively represent one mobile equipment, so if changing
mainboard , IMEI number should changed together.
IMEI composition
TAC: type approval code
FAC: final assembly code
SNR: serial number
SVN: software version number
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4GSM system theory
4.1 General
Below is the basic introduction of Global System for Mobile communications (GSM) cellular
network, which is just a brief introduction. If you want to know the detail technology, please refer
to the GSM_SPEC_PHASE 2+ .
4.2 The general concept of honeycomb
The cellular systems are now using in the EGSM and DCS frequency bands to provide
wireless telephone services. Comparing with the ordinary wireless telephone system, the
cellular networks have more calling service and system capacity. Ordinary wireless telephone
system’s each working channel should cover all the area, but the “honey comb” systems just
need to cover the several adjacent cells or just one cellular cell.
Each cellular cell has one Base Station (honeycomb station), with transmitting and receiving
equipment for a pair of frequencies (one channel). Because each cellular cell is much smaller, then
the Base Station and operating wireless telephone all have smaller power consumption than
ordinary system. Then the power of a specific channel is just confined in the cellular cell area,
sometimes extending to the direct adjacent cellular cells.
Because the a specific channe l in one cellular cell just confined in the small are a, then the
channel can be used in another cellular cell area beyond the first cell. Then several users can use
one channel in a big area, and don’t interfere with each other.
4.3 GSM introduction
Other than the analog cellular system, GSM system use digital wi reless technology, which
have below advantages:
International roaming --- because the international agreement and standardization, then the
GSM equipment can be used in any other country using GSM system.
Digital air interface --- There are all digital connections between the GSM telephones and
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the Base Stations, and the Base Station also digitally connect to switching system and PSTN.
ISDN compatibility --- ISDN is a kind of digital communication standard which will be
adopted by almost country all over the world and using the existing PSTN system to transmit the
digital voice data. GSM telephone is compatible to the ISDN.
Security and Secrecy --- The analog system is easy to eavesdrop using specific radio receiver, but the GSM system gets a big improvement because the data was digital
coding before transmitting.
Better voice quality --- The digital system is more effective to deal with the co-channel
interfere, transmission interrupt and multi-path fading, and voice quality can be improved by error
correct coding.
Efficiency --- GSM system is more efficient in using frequency spectrum than analog
system.
As figure 1 shows, bold line area indicate a overall area covered by a GSM system. The area
was divided into several small cellular cells, each cell has a cellular base station, each base station