system design

Ben Vallack walks through designing a custom keyboard PCB from scratch using Ergogen and KiCad, ending with a gerber file ready to order from a PCB fabricator. The example is a split keyboard.

Ben Krasnow of Applied Science shows how to make small batches of specialty glass with minimal equipment, including designing and making photochromic glass. He covers ingredients, melting and the challenges involved.

Matt Risinger covers installing a Zehnder ERV fresh-air system in a tight passive house, explaining balanced ventilation, the benefits of heat recovery and the costs involved.

The first stream in the Emacs From Scratch series, building a custom Emacs configuration from zero while teaching basics. It covers a usable baseline setup and the packages for completion, themes and productivity.

The first part of Robert Baruch's series on building a 6800 CPU on an FPGA with nMigen, a Python-based hardware description language. It introduces the HDL while implementing a simpler 6800 core.

Markus Triska tours Prolog's most distinctive features, including its use as a database and query language, rule processing, constraint solving and compile-time rewriting. It also covers concise meta-interpreters.

Alan Becker's short series on the 12 principles of animation, covering squash and stretch, anticipation, staging, timing, arcs, appeal and the rest. Each principle gets a brief animated illustration.

Russ Cox gives a 23-minute tour of the Acme text editor from Plan 9, showing its mouse-driven interface, executing commands from text, and its filesystem-based interface to other programs.

The first lesson of MangoJelly's FreeCAD 0.20 beginner course, covering setup, preferences and navigation. The series teaches fundamentals through complete workflows such as sketching, Part Design and STL export.

George Brocklehurst of thoughtbot demonstrates Vim's built-in completion mechanisms, from word, line and block completion to ctags. The aim is to type less and make fewer typos.

Tech Ingredients shows how to build flat panel speakers from exciters and foam board, with construction guidelines, measured SPL comparisons and a complete system playing music.

Tech Ingredients shows how to build cheap, high-performance flat-panel speakers using audio exciters on sheet materials such as foam-core board. It explains how distributed-mode speakers work and walks through experiments to find good designs.

Tech Ingredients builds a pair of large Voigt speakers and explains ported, transmission line and horn designs. It tests them in an anechoic chamber and uses constrained layer damping for the enclosure.