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This lesson is about repairing the speaker without sound
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Mainly from four aspects
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First, the code name, function and position of the speaker in the circuit diagram
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Second, the structure of the speaker-related circuit
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Third, the description of the circuit of the speaker in the schematic diagram
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Fourth, when there is no sound from the speaker, how to repair it
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First look at the code name and function of the speaker
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The picture on the right shows a modern loudspeaker
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Common codes in drawings are SPEAK and SPK
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Its function is to make sound, when making hands-free calls,
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when making video calls, when playing music, and when there are incoming calls
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It is a component that converts electrical signals into sound
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Its structure is actually relatively simple, the interior is a coil,
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the enameled wire of a certain wire diameter winds a certain number of turns along a certain direction,
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it has two poles
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This coil is placed in a permanent magnetic field, and the coil is glued to the membrane of the horn
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When a sound signal is communicated to it,
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it will drive the membrane to make a sound
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Next, look at the position of the speaker
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Take the Huawei P40 model as an example, its speaker is at the rear of the phone
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The speakers of all mobile phones are at the rear of the mobile phone
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Everyone here should pay attention, the current mobile phone has developed into a dual speaker,
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but the main speaker is located at the end of the mobile phone
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What problems can be caused if the speaker is damaged?
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It will cause no sound from the speaker, such as no sound when playing music
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You turn the volume up to the max and it doesn't make any sound
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Another problem is that the speaker does not make sound when there is an incoming call,
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and there is no sound for video calls
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Also, when we make a hands-free call, we can't hear the other party's voice
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These are the faults caused by the damage of the speaker or the related circuit of the speaker
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Next, let's look at the causes of speaker failure
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Ringtone amplifier chip is also called small audio
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The sound signal it outputs must be given to the speaker, and the speaker can produce sound
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In other words, the source of the speaker's sound signal is small audio, of course not the most source
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The small audio gives the sound signal to this speaker through the line
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During this process, if the line channel or components are faulty,
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the speaker will not be able to produce sound
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What is associated here is the small audio, the channel of the line, and the components
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What does this component contain?
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It contains speakers or small components, inductors, capacitors, or resistors
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That's all for this lesson
