high current

Lock-picking YouTuber Bill Johnson (BosnianBill) explains how to choose a high-security lock and why, showing examples and comparing designs. It covers what makes some padlocks more pick-resistant than others.

John Scholes builds a depth-first tree-search operator step by step in a Dyalog APL session. It covers higher-order functions and runs the search on the N-Queens problem.

Ben Krasnow of Applied Science shows how to make and test YBCO high-temperature superconductor with a kiln and eBay chemicals. He demonstrates flux pinning and shows a close-up of the crystal structure.

A step-by-step guide to building a lifter, a small triangular ionocraft made from balsa wood, aluminum foil and thin wire, powered by a high-voltage supply. It also shows high-voltage safety practices.

The Thought Emporium shows how to receive clear images directly from GOES-15, 16 and 17 and Himawari 8 geostationary weather satellites with software-defined radio. It covers the extra effort needed to receive GOES data.