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Questions and answers

What can I watch about repairing power supplies?

The rubric includes videos on repairing a charger and an example power-supply repair.

Are there videos explaining switching power supplies?

Yes. Topics include their components, input and output filters, and APFC.

Which measuring instruments are covered?

Topics include a USB tester, the EONE ET201 multimeter, and an oscilloscope.




Components, Part 2: Resistors and Their Variants
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Components, Part 2: Resistors and Their Variants

Components, Part 2: Resistors and Their Variants
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The resistor is probably the most common electronic component. I’d venture to say it’s also the oldest component still in use. So I’ll start my detailed look at different electronic components with resistors.
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A little about repairing a charger and the common-mode choke on a power supply output
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A little about repairing a charger and the common-mode choke on a power supply output

A little about repairing a charger and the common-mode choke on a power supply output
14 53511+4
A short video that could easily go in the “notes from the field” category.
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Components, Part 1: X Capacitors
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Components, Part 1: X Capacitors

Components, Part 1: X Capacitors
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With this article, I’d like to start a series about various electronic components: diodes, capacitors, resistors, varistors, and so on. There are so many different components, and I can’t shake the feeling that by the time I finish writing about them, something new will already have come out :) I’ll start with X-type capacitors, especially since this article is a follow-up to my previous article about Y capacitors.
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A Small Fan in Military-Grade Design
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A Small Fan in Military-Grade Design

A Small Fan in Military-Grade Design
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Many years ago, I picked up a fan with a rather unusual design. I tried to get it running back then, but had no luck, so I ended up putting it on a shelf. Now, after all this time, it’s turned up in my hands again.
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How to determine a transformer's power
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How to determine a transformer's power

How to determine a transformer's power
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I've been asked more than once how to determine the power rating of an unmarked 50 Hz transformer, so I'll try to explain and show a couple of examples.
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How switched-mode power supplies with APFC work
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How switched-mode power supplies with APFC work

How switched-mode power supplies with APFC work
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Some time ago, I was asked about the power factor correction circuit in switched-mode power supplies. I’ll try to briefly explain what it is and why it’s needed.
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USB tester or the finer points of Chinese mathematics
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USB tester or the finer points of Chinese mathematics

USB tester or the finer points of Chinese mathematics
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A short video showing why a USB tester should only be used for rough estimates, not precise measurements.
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Oscilloscope and power supply
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Oscilloscope and power supply

Oscilloscope and power supply
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A short video about safety when using an oscilloscope to repair and test switch-mode power supplies.
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One example of a power supply repair
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One example of a power supply repair

One example of a power supply repair
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Sometimes people bring me all kinds of devices to repair. This time, someone brought in an air conditioner control board with a preliminary diagnosis: the power supply had failed due to a voltage surge caused by a lightning strike.
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EONE ET201, 2-in-1 multimeter, video review
2 86700

EONE ET201, 2-in-1 multimeter, video review

EONE ET201, 2-in-1 multimeter, video review
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I decided to make a video version of my review of this unusual multimeter-oscilloscope, since some things are easier to show than explain in writing.
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How a Power Supply Works, Part 4
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How a Power Supply Works, Part 4

How a Power Supply Works, Part 4
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Today we'll look at the next stage after the inverter: the power transformer. This won't be a very long article, but I think it'll be useful.
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What a switching power supply consists of, part 3
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What a switching power supply consists of, part 3

What a switching power supply consists of, part 3
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Last time, I covered the input stage of a switching power supply, the bridge rectifier, and the filter capacitors. Now it’s time for the next stage: the inverter. This is the most complex and extensive part, but also the most useful.
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What a Switching Power Supply Is Made Of, Part 2
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What a Switching Power Supply Is Made Of, Part 2

What a Switching Power Supply Is Made Of, Part 2
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I’ve already posted videos about individual parts of a power supply, but after thinking it over, I decided I hadn’t done it the right way—or, more precisely, not in a very logical order—so I’m putting that right. With this article, I’m starting a short series called "How It Works", where I’ll go through all the sections of a typical switching power supply one by one, explain what they do, and point out where components can fail.
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Q&A, attempt one
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Q&A, attempt one

Q&A, attempt one
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I decided to answer a couple of questions people asked me in the comments on a video. This might be useful to other readers too.
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A video about one small but important capacitor
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A video about one small but important capacitor

A video about one small but important capacitor
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I’m often asked about the noise-suppression capacitor that connects the primary and secondary sides of a power supply. In this video, I’ll try to answer the questions of why it’s needed and which one is best to choose.
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Output Filters for Switching Power Supplies
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Output Filters for Switching Power Supplies

Output Filters for Switching Power Supplies
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A short video about power supply output filters.
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Input Filters for Switching Power Supplies
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Input Filters for Switching Power Supplies

Input Filters for Switching Power Supplies
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It all started when I decided to make a video about power supply filters and what they do. I gave it a try, but realized the topic was too big to cover in a single video, so I ended up splitting it into two parts. The first part is about the input mains filter.
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How to turn a KRENka into a switching converter
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How to turn a KRENka into a switching converter

How to turn a KRENka into a switching converter
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A real-world example of using a linear regulator to build a switching converter.
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