In this video I’ll be assembling and reviewing the LM358-based soldering kit form Aliexpress/ebay.
It uses the double opamp to generate a square wave that feeds a transistor which in turn powers LEDs.
The one I bought can be found here:
Blue Led 5MM Light LM358 Breathing Lamp Parts Kit Electronics DIY Interesting Product Suite
On My Way Kevin MacLeod (incompetech.com)
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