Uploaded November 2022 | Updated September 2026, 2 weeks ago

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The circuit inside a microwave oven is a half-wave doubler, an incredibly inefficient design. How does it work? Why do we put them in microwaves?!

Huge thanks to Mehdi Sadaghdar (ElectroBOOM) for the consult:
youtube.com/@ElectroBOOM
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VIDEO ANNOTATIONS/CARDS

Alternating Current:
youtu.be/7weMCsff0xw

Capacitors Explained:
youtu.be/zYRx6Zub3cA
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RELATED YOUTUBE VIDEOS

EEVblog on Scope Safety:
youtu.be/xaELqAo4kkQ

Eugene on Rectifiers:
youtu.be/J8A6QUxfk8c

Hawley Hobbies's 6000 Volt Power Supply:
youtu.be/OBQTBgFjFsQ
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electronics.stackexchange.com/questions/24208/how-does-the-villard-circuit-double-voltage
doi.org/10.1051/jphystap:019010010002801
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LINKS TO COMMENTS

youtube.com/watch?v=nSJtzn2H3Do&lc=UgxbWstCHiy9tmCV6tl4AaABAg
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TIME CODES

00:00 Cold Open
00:45 Half-Wave Rectifiers
01:44 Giant Transformer
02:42 Giant Capacitor
04:12 ElectroBOOM Rant
05:35 Low-Voltage Analog
06:32 Diodes
07:36 The Capacitor's Purpose
09:17 Half-Wave Doublers
10:20 Summary
10:54 Outro
11:28 Featured Comment
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Corrections:

01:32 "Utilization" would have been a better word than "efficiency." Half-wave rectifiers have a 50% utilization, not a 50% efficiency. They only utilize 50% of the provided voltage.

01:57 Phone chargers from the 1990s and early 2000s were simple transformers. Modern phone chargers are a more complicated design called an "Switch Mode Power Supply" or SMPS.