electronics

Techmoan demonstrates the Tefifon, a vintage German audio player that combines elements of record and tape with a grooved elastic loop. He shows how it works and plays it.

Mike of mikeselectricstuff shows his heavily modified old BBC Micro system in a 28-minute tour of 8-bit hardware archaeology.

Shahriar of The Signal Path tears down and experiments with Keysight's UXR real-time oscilloscope, which offers 110GHz bandwidth and 256GS/s sampling, and compares architectures from Keysight, LeCroy and Tektronix.

Sean Hodgins shows the build of the Arduino-based glitter bomb package-theft trap he made with Mark Rober, covering the electronics and the problems that came up. The code and schematics are on GitHub.

Afrotechmods plays with 2600F ultracapacitors that can dump hundreds of amps, shorting them to vaporize bits of metal. Along the way he explains the three most important capacitor equations. The uploader warns that the capacitors are not designed to be shorted.

Jeri Ellsworth demonstrates a PMOS transistor she fabricated herself in a home chip lab. She shows some of its electrical characteristics.

mitxela shows his KiCad plugin that rounds PCB tracks to give circuit boards organic, melted-looking layouts instead of rigid geometric ones.

A short tour of the Megaprocessor, a microprocessor built at enormous scale from tens of thousands of discrete transistors. The builder shows what the machine is made of and where it now lives, at the Centre for Computing History in Cambridge, where visitors can play Tetris on it.

Marco Reps builds and tests an open-source 8.5 digit voltmeter based on CERN's high-precision ADC design. The video walks through assembly, soldering and measurement of the resulting instrument.

Styropyro tests an eBay laser tattoo removal device and finds it is a roughly million-watt pulsed laser, powerful enough to ignite air in the beam. He had bought it hoping to salvage an Nd:YAG laser cavity.

A three-minute demo of a series circuit with three LEDs that behaves in a surprising way, posed as a question of how it works.

Dave Jones of EEVblog investigates why a 4K BenQ monitor switches itself off, tracing it to static discharge from an office chair. He uses an oscilloscope to examine the static impulses.

Electronics hobbyist bigclivedotcom tears down a cheap USB power supply with a manufacturing fault that carries full mains voltage to the USB ports, showing the risk of electric shock.

A short Google Japan promotional video, in Japanese, for Gboard Double-Sided, a keyboard with no back side that comes in a paper-craft version and a full electronics version. It is a playful April-Fools-style product concept.

Big Clive does a complete teardown of a lithium phone battery, taking apart the protection circuit, case and the cell itself. He notes it was risky because the cell was not discharged first.

Big Clive tears down a smart meter with a wireless modem found among fly-tipped materials. He examines its internals and checks conspiracy claims about microphones, cameras and 5G.

Big Clive tears down a cheap eBay digital caliper, explaining its capacitive linear encoder and measuring its quiescent current. He finds it surprisingly accurate and repeatable for its price.

Dave Jones of EEVblog tears down a fake Apple A1265 USB charger and shows the shortcuts that make it unsafe, such as poor isolation.

AlphaPhoenix builds a scaled-down version of the Veritasium electricity thought experiment using about a kilometer of wire and an oscilloscope. He measures how the signal actually propagates and explains the result.

A maker's time-lapse of building a working computer inside a LEGO-style brick, using a tiny 0.42-inch OLED screen, with a demo at the end.

Sam Zeloof shows the upgraded second iteration of his homemade silicon integrated circuit fabrication process, producing chips with around a thousand transistors in his garage. It is a short overview of what the home fab can now do.

Johnny Lee demonstrates head tracking with a Wii remote and a head-mounted pair of IR LEDs, so a screen acts like a window into a 3D scene as your head moves.

Linus Akesson demonstrates the Commodordion, a fully functional 8-bit accordion built around Commodore 64 hardware with bellows made of floppy disks. He performs Scott Joplin's Maple Leaf Rag and tells the story of the build.

Technology Connections experiments with filtering white and colored LEDs to make holiday lights look less garish. He explains why narrowband LED strings look harsh compared with incandescent bulbs.

The Thought Emporium builds a homemade multi-electrode array, grows human neurons on it and attempts to take readings. It is the first part of a series aimed at connecting living neurons to a computer.

A Plogue developer shows the custom electronic test rigs built to measure the Sega Mega Drive/Genesis sound chip (YM2612) for the chipsynth MD emulation. It covers the years of testing and reverse engineering needed to reproduce the chip's quirks accurately.

Ben Krasnow of Applied Science builds and operates a simple mass spectrometer, using it to measure potassium isotopes in a salt substitute. He explains the design choices and the theory behind it.

A two-minute demo of SmartKnob View, an open-source input knob built from a brushless gimbal motor, magnetic encoder and round LCD. Closed-loop torque control gives software-defined detents and end stops.

Jeff Geerling looks at a Sharp NEC commercial display with a slot for a Raspberry Pi Compute Module. It is a large screen without built-in smart TV features or tracking.

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.

LightningOnDemand revives a pulsed Lorentz plasma cannon, using modern capacitors to extend its range and increase the delivered energy. It is a high-voltage, high-current hobby demonstration.

Google ATAP's 2015 introduction to Project Soli, a radar-based sensor on a chip that tracks sub-millimeter hand motions for gesture interaction in small devices.

Tom Scott shows a full-size real-life emoji keyboard built from 14 keyboards and over 1,000 hand-placed stickers, covering all of Unicode 8.

A short demo of typing on the Modos Paper Monitor, an open e-ink monitor, using 4-level grayscale to show low latency.

A short video of the first TRON Smart House, built in 1989 as a demonstration of ubiquitous and ambient computing in the home. It comes from the uID Center, which promoted the TRON architecture.

The 8-Bit Guy reviews the Color Maximite 2, a modern ARM-based computer that boots straight into BASIC. He shows what it can do as a retro-style machine.

Ben Krasnow of Applied Science shows that a plain laser diode can measure sub-micron vibrations from centimeters away using self-mixing interferometry, and can also be used for range-finding.

A hobbyist builds a prototype full-frame CCD camera from scratch, with open-source design files and a custom PCB. The video shows the first, still rough prototype.

CNLohr maps Wi-Fi signal strength at high resolution by moving an ESP8266 on a CNC mill, then visualizes the 3D data in WebGL. The result shows interference patterns in space.

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.