Have you heard of the Sprengel pump? It’s how they drew hard vacuum back before mechanical pumps were perfected — the first light bulbs had their vacuums drawn with Sprengel pumps, for example. It worked by using droplets of a particular liquid to catch air particles, and push them out a narrow tube, thereby slowly […]
Why build a telescope? YOLO, as the kids say. Having decided that, one must decide what type of far-seer one will construct. For his 10″ reflector, [Carl Anderson] once again said “Yolo”— this time not as a slogan, but in reference to a little-known type of reflecting telescope. Telescope or sci-fi laser gun? YOLO, just […]
For most people, experimentation with film photography comes in the form of the 35 mm format. Its ubiquity in snapshot photography means cameras are readily available at all levels, and the film offers a decent compromise between resolution and number of shots per dollar spent. For those who wish to take their film photography further […]
In theory, all parts are ideal and do just exactly what they say on the box. In practice, everything has its limits, most components have non-ideal characteristics, and you can even turn most parts’ functionality upside down. The Component Abuse Challenge celebrates the use of LEDs as photosensors, capacitors as microphones, and resistors as heat […]
Off to the races? Formula One races, that is. This project by [mazur8888] uses an ESP32 to keep track of the sport, and display a “live” dashboard on a 2.9″ tri-color LCD. “Live” is in scare quotes because updates are fetched only every 30 minutes; letting the ESP32 sleep the rest of the time gives […]
The Estes line of flying model rockets have inspired an untold number of children and adults alike, thanks in part to their simplicity. From the design and construction of the rockets themselves to the reliability and safety of the modular solid-propellant motors, the company managed to turn actual rocket science into a family activity. If […]
We often marvel at the many things a 555 can do. But [Zafer Yildiz] shows us that it can even take the place of a PCB. You’ll see what we mean in the video below. The timer relay circuit is built “dead bug” style with the 555 leads bent out to provide wiring terminals. Honestly, […]
To connect the miniature world of integrated circuits like a CPU with the outside world, a number of physical connections have to be made. Although this may seem straightforward, these I/O pads form a major risk to the chip’s functioning and integrity, in the form of electrostatic discharge (ESD), a type of short-circuit called a […]
Over on his YouTube channel our hacker [GrandpaAmu] liberates a collapsible chair from a single piece of wood. With the assistance of an extra pair of hands, but without any power tools in sight, this old master marks up a piece of wood and then cuts a collapsible chair out of it. He uses various […]