swept frequency

Dave Jones of EEVblog demonstrates that a frequency counter can detect gravity through the 2g tipover effect on quartz crystal oscillators. He shows the reading shift as the instrument's orientation changes.

Disney Research presents Touche, a swept frequency capacitive sensing technique that recognizes complex hand and body configurations, and adds touch sensitivity to humans, liquids and everyday objects.

A two-minute sine tone sweeping exponentially from 20 Hz to 20 kHz, covering the human hearing range at constant acoustic pressure.

Vsauce's explainer on Zipf's law, the pattern in which the frequency of a word is inversely related to its rank. It shows the pattern across many domains and discusses why it remains unexplained.

A VPRO documentary on quantitative analysts who designed the mathematical models and high-speed trading systems behind modern finance. It features figures such as Paul Wilmott and asks what risks come from treating markets as a machine.

Tom Scott visits IEX, a stock exchange that slows down trading with a long coil of fiber. The coil removes the speed advantage of high-frequency traders.

Amazon's Jon Jenkins at Velocity 2011 on how operations can drive revenue and on Amazon's highly available, autonomous architectures. It includes details on deployment frequency and Amazon's move to AWS.

Clip from The Dark Knight in which Batman uses a sonar-based system that turns phones into a city-wide surveillance network.

Not Just Bikes explains why Swiss trains are considered among the best in Europe and the world, covering frequency, connections and what riding them is like.

3Blue1Brown's animated visual introduction to the Fourier Transform, showing how a signal breaks into frequency components.

3Blue1Brown shows how the uncertainty principle arises from Fourier transforms. A wave packet cannot be narrow in both position and frequency, so the principle is a property of waves rather than of measurement.

Optiver's Carl Cook explains how to build high-frequency trading systems in C++, where the critical path runs rarely but must be extremely fast. He covers techniques for low and predictable latency, including avoiding main memory and cache misses.

Benn Jordan investigates infrasound and low-frequency noise from data centers, including xAI's Colossus and a crypto mine, and reports his own experiments on the effects. The video covers the health and community impacts on nearby residents.

A short film by Max Joseph about his anxiety in bookstores and how to read more books amid constant streaming, social media and news. He looks for ways to rebalance his content diet in favor of reading.

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.

Tom Scott explains Electrical Network Frequency analysis, where hum from the power grid in a recording is matched against grid logs to date and place it. He talks to a researcher and sets them a challenge.

Adam Tornhill's GOTO Copenhagen 2019 talk on how to prioritize technical debt in large codebases. It argues for combining code complexity with change frequency (hotspots) from version control data, rather than trying to quantify debt in the abstract.

A short clip of Venetian Snares' track 'Look' from Songs About My Cats (2001), shown as a spectrogram. The audio encodes an image in its frequency content.

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.