A hand holding the circuit in its active state

2025 Component Abuse Challenge: A Self-Charging LED Flasher By Burkhard Kainka

[Tito] entered a Self-Charging LED Flasher into the Component Abuse Challenge. It’s a simple re-build of a design by the unstoppable [Burkhard Kainka], and while [Tito] doesn’t explain its workings in detail, it’s a clever experiment in minimalism, and a bit of a head-scratcher at the same time.

You press a button and an LED flashes.  But there is no battery, so how does it work? Maybe the schematic to the right here will help. Or does it confound? Look at it yourself before reading on and see if you can figure out how it works.

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Self Driving Potato Hits The Road

Potatoes deserve to roam the earth, so [Marek Baczynski] created the first self-driving potato, ushering in a new era of potato rights. Potato batteries have been around forever. Anyone who’s played Portal 2 knows that with a copper and zinc electrode, you can get a bit of current out of a potato. Tubers have been powering clocks for decades in science classrooms around the world. It’s time for something — revolutionary.

[Marek] knew that powering a timepiece wasn’t enough for his potato, so he picked up a Texas Instruments BQ25504 boost converter energy harvesting chip. A potato can output around 0.4 V at 0.6 mA. The 25504 uses this power to slowly charge a capacitor. Every fifteen minutes or so, enough energy is stored to power a motor for a short time. [Marek] built a car for his potato — or more fittingly, he built his potato into a car.

The starch-powered capacitor moves the potato car about 8 cm per cycle. Over the course of a day, the potato can travel around 7.5 meters. Not very far, but hey, that’s further than the average potato travels on its own power. Of course, any traveling potato needs a name, so [Marek] dubbed his new pet “Pontus”. Check out the video after the break to see the ultimate fate of poor Pontus.

Now that potatoes are mobile, we’re going to need a potato detection system. Humanity’s only hope is to fight fire with fire – break out the potato cannons!

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