EEVblog® Electronics Community Forum
Products => Other Equipment & Products => Topic started by: DavidAlfa on March 19, 2022, 11:16:13 am
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Saw a good offer and I couldn't resist (3-day shipping for $25), I bought one to clean stuff.
Not sure of its capabilities, I barely have used it, just dropped some water and turned it on. Crazy noise came out, guess it's working.
I checked several schematics but they were all different, so I reverse-engineered it during the breakfast (Was a quite long breakfast :D) and they are, attached for the curious.
Switching between 35/50W modes is done by simply rectifying half or full-wave, as the output capacitor is just 1uF it won't filter much...
I replaced C1B with 10uF, the operation seems more powerful and considerably way less noisier due the reduced mains modulating the ultrasonic waves (But the transistors overheated, so don't do it).
Edit: It blowed up today (Nothing serious, water seeped in and burned a track, no parts damaged), while fixing it I noticed some parts had wrong reference numbers. Fixed.