tech-air

A University of Michigan Medicine demonstration of building a cheap DIY air purifier from a box fan and a HEPA or high-MERV filter using hardware-store parts. It explains why this helps against dust, smoke and viruses and ties it to local air quality readings.

In this American Masters clip, Jacques Pepin shows two different techniques for making a perfect omelet, a dish he is famous for teaching America.

James Hoffmann demonstrates his technique for a clean, sludge-free cup from a French press: stir, break the crust, wait, and carefully pour. It is a four-minute guide.

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.

Jacques Pepin makes a classic French omelette in a short uncut demonstration. The video contrasts it with the American style.

Dr. Mark Cucuzzella of the Natural Running Center gives a short instructional video on natural running form. It describes the principles of good technique, including barefoot-style mechanics.

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.

James Hoffmann demonstrates his recommended technique for brewing coffee with a Hario V60 or other cone-shaped dripper, with notes on water and filter papers.

Tech Ingredients builds a pair of large Voigt speakers and explains ported, transmission line and horn designs. It tests them in an anechoic chamber and uses constrained layer damping for the enclosure.

Jacques Pepin demonstrates deboning a whole chicken, quickly and with complete control. It is a short, wordless-feeling technique demo that shows a skill most cooks never learn.

Matt Risinger demonstrates a blower door test on a house, using a fan to measure air leakage and find where air gets in and out. It shows how the test reveals the quality of the build.

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 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.

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.

Technology Connections shows a cheap method for capturing analog video: a composite-to-HDMI upscaler feeding an HDMI capture dongle, aimed at digitizing home movies and VHS tapes.

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 short promotional video demonstrating a head-thumping technique that is claimed to relieve tinnitus. Covering the ears and tapping the back of the head is said to silence the ringing temporarily.

Inigo Quilez live-codes the "Happy Jumping" animated scene in a Shadertoy GLSL shader over about six hours. He builds the raymarched character step by step, explaining the math and procedural techniques, with checkpoints linked for each stage.

A two-hour NANOG tutorial by Richard Steenbergen aimed at network engineers, covering optical networking technologies. This is the updated 2017 edition of a recurring talk.