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A roughly 90-minute film of John Dobson building a Dobsonian telescope step by step, including hand-grinding the mirror.

DIY Perks shows how to turn old or smashed TVs and monitors into realistic artificial window lights, using the backlight and Fresnel lens to simulate distant daylight.

Tech Ingredients shows how to build flat panel speakers from exciters and foam board, with construction guidelines, measured SPL comparisons and a complete system playing music.

Tech Ingredients shows how to build cheap, high-performance flat-panel speakers using audio exciters on sheet materials such as foam-core board. It explains how distributed-mode speakers work and walks through experiments to find good designs.

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.

A 1993 Yoga Works video of the Ashtanga Yoga Primary Series led by Sri K. Pattabhi Jois, with senior students demonstrating. The class is filmed in classic style from the back of the room.

ElectroBOOM's Mehdi Sadaghdar explains how a full bridge rectifier works, the building block of AC to DC converters, with his usual humor and a demonstration of the circuit.