radio waves

A short video from the trafficwaves.org site showing how traffic jams and standing waves form, including the fight between cheaters and blockers at an exit-lane backup. It also touches on how individual driving behavior affects the flow.

Technology Connections explains why the superheterodyne radio has its name and how mixing frequencies lets it tune stations well. It walks through the underlying wave phenomena and algebra and why the design solved a hard tuning problem.

Remastered episode of Tim Hunkin's The Secret Life of Machines about the radio, covering its development including Hertz and Marconi experiments and Armstrong's FM radio in animated form.

The Thought Emporium tests so-called negative ion and anti-5G wellness products and finds they are radioactive, with some coated in powdered thorium.

Two experimenters hold blades of grass near a radio transmitter antenna and hear the AM station through the arc between antenna and grass. It is a short, informal demonstration of unintentional AM demodulation.

A one-minute clip where an AM radio station can be heard through the arcing of a high-power transmitter tower.

Five hours of the late-night BBC Radio 4 Shipping Forecast, uploaded to mark its 150th anniversary. It can be used as sleep audio or to learn the sea areas named in the broadcast.

A one-minute clip from a 2016 Toronto conference in which Geoff Hinton comments on deep learning and radiology. He suggests radiologists should stop being trained because machines would soon read scans better.

The BBC radio play adaptation of William Gibson's cyberpunk novel Neuromancer, running about two hours. It features professional voice acting, sound effects and music.

A PBS clip in which Richard Feynman explains the strange nature of light and electromagnetic radiation. He conveys how little of it we actually see and how radio waves are present everywhere.

A five-minute CBC Radio WireTap farewell video in which people of all ages offer words of wisdom to younger people. The advice is short and funny, and keeps coming back to the point that nobody really knows what they are doing.

Veritasium explains in detail how LIGO detects gravitational waves, with a laser interferometer measuring displacements smaller than a proton. The video focuses on the extreme precision and the techniques needed rather than the general discovery story.

Veritasium visits Chernobyl, Fukushima and other places to find who on Earth is exposed to the most ionizing radiation. The answer turns out to be surprising and puts radiation risk in context.

CNLohr explains how he made an ESP32 produce valid LoRa packets without a LoRa radio, using aliasing and clever signal tricks. It walks through the RF math and shows how far the signals reach.

A YouTuber explores the Chernobyl zone in 2013, takes a gamma spectrum of a hot reactor fuel fragment, and jokes about a radioactive ant bite. It is a hands-on amateur look at radiation in the exclusion zone.

A short demonstration of radioteletype (RTTY), a digital communication mode used in amateur radio, showing what the signal sounds like.

A Bell Labs film in which Dr. J.N. Shive uses a mechanical wave machine to demonstrate reflection, standing waves, resonance and impedance matching. He includes some equations but relies mostly on real-world examples a layperson can follow.

A tour of the historic WLW transmitter facility in Mason, Ohio, recorded at Hamvention 2013. It shows the surviving equipment from the 500,000 watt AM era, when WLW was the only US station at that power, and explains the history.

An episode of the Well There's Your Problem podcast on the 1987 Goiania radiological accident in Brazil, based largely on the IAEA report. It goes through the event day by day.

A 1979 CBC radio interview in which Ted Nelson tries to explain how computers could serve as tools for thinking and visualizing. The interviewer keeps failing to grasp the idea, and Nelson patiently answers again and again.

ElectroBOOM examines whether 5G and other electromagnetic waves can harm people, explaining the EM spectrum and the difference between ionizing and non-ionizing radiation. It includes experiments and measurements in his usual humorous style.

The Thought Emporium follows up on his earlier video showing negative ion products are radioactive, reporting that Amazon pulled listings and companies shut down. He tests more radioactive quack products with a Geiger counter and cloud chamber.

President Reagan's 1987 radio address on free and fair trade, in which he argues for free trade over protectionism.

A 1971 DEC LAB-8/e (PDP-8/e) minicomputer plays music by inducing noise into a nearby AM radio. The software is Richard Wilson's 1975 Music Compiler running under OS/8.

Amateur footage of a Japanese coast guard boat riding up and over large tsunami waves after the March 2011 Tohoku earthquake. It is short and unedited.

A one-minute demo at the Computer History Museum's IBM 1401 restoration lab, where a program makes the machine's radio-frequency interference play tunes on an AM radio.

A satirical CBC Radio This Is That sketch profiling a Vancouver artisanal firewood company that sells bundles of kindling for $1000.

Veritasium explains why a halved grape in a microwave makes plasma: the grape traps microwaves, and the fields of two halves interact to concentrate energy where they touch.

Tom Scott investigates the claim that the microwave was invented to heat hamsters, and interviews James Lovelock about freezing and microwave-thawing hamsters in the 1950s. It traces early magnetron uses beyond radar.

An animated visualization of basic quantum mechanics using a free particle, with simulations based on the actual equations. It covers waves, particles, and how measurement collapses the wavefunction.

3Blue1Brown visualizes Feynman's lecture on the refractive index, explaining why light appears to slow down in glass and why the effect depends on color. It builds the idea from waves produced by oscillating charges in the material.

Veritasium tells how Kodak film was fogged by radioactive fallout from the first atomic tests, letting the company detect nuclear testing before anyone announced it. The video also covers the deal to keep it quiet and how fallout contaminated packaging.

Huygens Optics shows how DIY photon sieves shape a laser's wave front, explaining how they differ from zone plates and how aperture count affects the focal point, with time-resolved visualizations of the diffraction.

Huygens Optics explores the idea that space is a non-linear elastic medium, and uses simulations to show how wave energy might be confined locally into particle-like objects. It touches on inertia, the Schwinger limit and the vacuum as a medium.

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.

A short Stanford video in which Chao-Lin Kuo surprises Professor Andrei Linde with BICEP2 evidence supporting cosmic inflation, the first apparent images of primordial gravitational waves.

Tech Ingredients demonstrates how microwaves work and how they affect objects at range, then shows ways to defend against them. It includes a correction about rectifier output frequency.

NileRed makes radioactive uranium glass from scratch, showing the chemistry involved and the green fluorescence under a blacklight. The video includes warnings about handling radioactive material.

James Houston's entry to Radiohead's Nude remix contest, performing the 6/8, 63bpm song on obsolete hardware such as hard drives, a dot matrix printer, a scanner and a ZX Spectrum.

A one-minute New Scientist clip showing a Japanese experiment in which drivers on a circular track produce a spontaneous traffic jam that travels backward. It illustrates phantom traffic jams without any obstacle.