Xerox Phaser 6180MFP, Руководство по обслуживанию

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2-90 Phaser 6180MFP Multifunction Printer Service Manual
Theory of Operation
Fax System
Telephone System Overview
Converting and Sending Voice in the Form of Electrical Signals
The human voice is a sound wave; in other words, air vibrations. Conversation
between two people results when such vibrations travel through the air and
reach each other’s ears. A string telephone transmits the sound wave
generated between two people along a string stretched tight, thus allowing
conversation over a distance. In this system, a paper cup at one end of the
string receives the sound wave, which are then transmitted along the string. A
paper cup at the other end of the string transmits them back to the air, so that
they again become audible sound waves.
A telephone is a device that replaces the vibrations transmitted by string with
electrical signals. The two paper cups correspond to microphone, speaker,
and the string to the telephone line. Because electrical signals travel over the
telephone line at a high speed with minimal attenuation, the telephone
enables conversation over great distances.
Voice is changed into electrical signals using electromagnetic induction, a
process by which electrical signals are generated by vibrating a coil in a
magnetic field. Both the microphone and speaker utilize this process. The
microphone transduces sound into electrical signals using electromagnetic
induction that occurs as a moving coil coupled to a diaphragm picking up
sound wave.