old computers

Dave Jones of EEVblog shows hand soldering of surface-mount parts, including drag soldering and tack-and-reflow of 0.5mm fine-pitch ICs, with solder paste and hot air.

A three-minute demonstration of professional hand-soldering techniques for multi-lead surface mount parts, to IPC class 3 criteria.

A 1953 US Navy training film on the basic mechanisms in fire control computers: shafts, gears, cams and differentials. It shows how these mechanical parts compute ship and target firing solutions.

A This Old House segment where Richard Trethewey installs a heat exchanger that uses waste heat from a central air conditioner to heat a swimming pool.

An 11-minute guided Wim Hof breathing session built around an expanding and contracting bubble to pace the breath. Wim breathes along with the viewer over ambient sound.

Dave Jones builds the Evil Mad Scientist discrete-component 555 timer kit, then tests it and explains the internal circuitry of the 555 at transistor level. He finishes with scope waveforms.

Wim Hof guides viewers step by step through his breathing method, with some explanation of the science he cites behind it. It stresses learning from the source and avoiding unsafe settings.

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.

A roughly 45-minute vintage US military instructional film that gives a comprehensive overview of celestial navigation, covering sextant use and the theory behind lines of position.

Ben Eater shows how to build logic gates out of transistors, including NOR gates. It is part of his clear hardware-from-scratch teaching style.