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Recognition and Measurement of Electronic Components

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This video mainly explains the principle of judgment and replacement of diodes

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When judging whether a diode is good or bad,

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first perform a visual inspection

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For example, in the picture, the diode has been burnt,

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like this, just replace it directly

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If the appearance is normal,

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you need to use a multimeter to judge whether the diode is good or bad

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First, adjust the multimeter to the diode range,

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measure the positive pole of the diode with the red marker,

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and measure the negative pole with the black marker

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The measured value is around 200

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Then change the test markers,

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then the measured value is OL

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Diodes need to be measured twice to prove good

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If the measured diode has a value after changing the test markers,

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it also means that the diode is damaged

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The values are not accurate when measured on the mainboard

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To make an accurate judgment, you need to remove the diode to measure

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When measuring the anti-static diode, the positive measurement value is about 500-800,

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and the value will also display OL if the markers are changed

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Principles of Diode Substitution

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In the mobile phone mainboard,

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the diode is relatively small and the power is relatively small

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So when replacing, just find the same size

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Precautions for Diode Replacement

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The power and size of the diodes in the iPad are relatively large,

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and the diodes on the mainboard of the mobile phones cannot be used instead

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It is recommended to replace the diode with the same parameters

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Diode parameters can be viewed through the schematic diagram

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Like in the Android drawing, if there is no parameter identification,

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you can try to replace it with the same size,

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or find the diodes with the same material version and the same position to replace it

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Ok, that's all for this video