eInk PDA Revisited
https://hackaday.com/2025/04/22/eink-pda-revisited/

In the dark ages, before iOS and Android phones became ubiquitous, there was the PDA. These handheld computers acted as simple companions to a computer and could often handle calendars, …read more (https://hackaday.com/2025/04/22/eink-pda-revisited/)

How Supercritical CO2 Working Fluid Can Increase Power Plant Efficiency
https://hackaday.com/2025/04/22/how-supercritical-co2-working-fluid-can-increase-power-plant-efficiency/

Multi-stage steam turbine with turbo generator (rear, in red) at the German lignite plant Boxberg (Credit: Siemens AG)
" data-medium-file="https://hackaday.com/wp-content/uploads/2023/04/Turbogenerator01.jpg?w=400" data-large-file="https://hackaday.com/wp-content/uploads/2023/04/Turbogenerator01.jpg?w=800">Using steam to produce electricity or perform work via steam turbines has been a thing for a very long time. Today it is still exceedingly common to use steam in …read more (https://hackaday.com/2025/04/22/how-supercritical-co2-working-fluid-can-increase-power-plant-efficiency/)

Virtual Nodes, Real Waves: a Colpitts Walkthrough
https://hackaday.com/2025/04/22/virtual-nodes-real-waves-a-colpitts-walkthrough/

If you’ve ever fumbled through circuit simulation and ended up with a flatline instead of a sine wave, this video from [saisri] might just be the fix. In this walkthrough …read more (https://hackaday.com/2025/04/22/virtual-nodes-real-waves-a-colpitts-walkthrough/)

A Scratch-Built Commodore 64, Turing Style
https://hackaday.com/2025/04/23/a-scratch-built-commodore-64-turing-style/

Building a Commodore 64 is among the easier projects for retrocomputing fans to tackle. That’s because the C64’s core chipset does most of the heavy lifting; source those and you’re …read more (https://hackaday.com/2025/04/23/a-scratch-built-commodore-64-turing-style/)

Unsolved Questions in Astronomy? Try Dark Matter!
https://hackaday.com/2025/04/23/unsolved-questions-in-astronomy-try-dark-matter/

A false colour image looking towards the Central Molecular Zone near the center of our galaxy. (JPL/Caltech)
" data-image-caption="" data-medium-file="https://hackaday.com/wp-content/uploads/2025/04/massivestars.jpg?w=400" data-large-file="https://hackaday.com/wp-content/uploads/2025/04/massivestars.jpg?w=800">Sometimes in fantasy fiction, you don’t want to explain something that seems inexplicable, so you throw your hands up and say, “A wizard did it.” Sometimes in astronomy, instead of …read more (https://hackaday.com/2025/04/23/unsolved-questions-in-astronomy-try-dark-matter/)

To See Within: Detecting X-Rays
https://hackaday.com/2025/04/23/to-see-within-detecting-x-rays/

It’s amazing how quickly medical science made radiography one of its main diagnostic tools. Medicine had barely emerged from its Dark Age of bloodletting and the four humours when X-rays …read more (https://hackaday.com/2025/04/23/to-see-within-detecting-x-rays/)

Open Source Commercial Synthesisers You Will Love
https://hackaday.com/2025/04/23/open-source-commercial-synthesisers-you-will-love/