Geely EC715 2009, Workshop Manual

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11.2.3 System Working Principle
11.2.3.1 System Working Principle
Radio:
Turn the radio control switch to "AM" and "FM", the antenna
module receives the radio signal and transmits to the radio
control through dedicated circuit. Radio control receives radio
signals through the internal filter circuit, transfers out to the
channel. Audio signal is amplified through the amplifier and
eventually through the IP32 terminal output terminals
2-6,1-5,3-7,4-8 to each speaker.
CD player:
Turn the radio control switch to CD mode, the radio control
assembly controls the CD movement. CD system mainly
consists of the laser and turntable system, servo system, signal
processing system, information storage system and control
system, etc.. CD player laser is a key component, which
consists of semiconductor lasers, optical system and electrical
detector component. It is a low-power laser diodes. Laser beam
is sent through the optical lens system onto the LP information
surface. The disc has a number of pits, when the beam hit the
pit, because of the reflected light is weak, photoelectric detector
picks up weak signals; when the beam hit the smooth aluminum
surface, there will be a strong reflected light. The detector's
high or low electrical pulse output signal corresponds to the
presence or absence of the pits. Through the RF amplifier and
the internal comparator, "1" and "0" serial digital signals are
obtained, and added to the digital signal and processing circuit
to carry out demodulation, frame sync detection, error
correction. The processed data will be added to the digital-
analog conversion (D / A) and converted into analog sound
output to the amplifier. The amplified audio signals will be sent
to each speaker through the radio control wiring harness
connector IP32 terminals 2-6,1-5,3-7,4-8.
11-12 Audio Entertainment System Body Electric
EC718/EC718RV EC715/EC715RV 10/2009