The working principle of microphone: the diaphragm is vibrated by human voice through the air, and then the electromagnetic coil wound on the diaphragm and the magnet around the moving wheat head form a magnetic field for cutting, forming a weak fluctuating current. The current is sent to the speaker, and then the fluctuating current becomes sound in the opposite process.
Working principle of microphone: When people speak into the microphone, sound waves make the diaphragm vibrate, and the diaphragm suddenly squeezes carbon particles, and the resistance changes accordingly, resulting in a current that changes with the sound vibration in the circuit, that is, the microphone is equivalent to a variable resistance.
Working principle of the receiver: When the current with different strengths is emitted from the microphone with the vibration of sound, the attraction of the electromagnet to the iron plate changes, which makes the iron plate vibrate and produces the same sound as the other party's voice, that is, the receiver is equivalent to an electromagnet.
Extended data
Basic characteristics of loudspeaker
(1) The speaker has two terminals (two leads). When a single speaker is used, the two pins have no positive polarity or negative polarity, and when multiple speakers are used at the same time, the two pins have polarity.
(2) The speaker has a paper basin, which is usually black and white.
(3) Speakers are round, square and oval.
(4) The back of the paper basin of the speaker is a magnet, and the external magnetic speaker will feel the presence of magnetism when touching the magnet with a metal screwdriver; The built-in magnetic speaker does not feel this way, but there is a magnet inside the shell.
(5) The loudspeaker is installed on the machine panel or in the sound box.