I used the excellent Quick KICAD Library Component Builder recently to build a new component for eeschema in KiCAD, but when I imported the library, I got an error dialog that said, “Library component load error error <error <pin only…
Before I placed my order, I had questions about Seeed Studio Fusion PCB service turn-around time for shipping to the USA, and so I figure others might as well. Here are details of my order of the ten 5cm square…
Math Monday came early this week, and we had some fun exploring Reuleaux triangles. Next to a circle, they’re the simplest curve of constant width you can make — that basically means you can roll a plank on top of…
I love getting photos of chess and checker boards that people have built using my tutorial (), or after being inspired by it, and so I’ve decided to start asking permission to post those photos and the stories behind them…
Here’s an Arduino-compatible GI-SP0256-AL2 speech synthesizer module that I’m finishing up. It’s a great 1980’s-era allophone speech synthesizer chip that was used in Intellivision expansion modules and sold at RadioShack stores for years for about $12. You can still find…
We finished up PopsicleBot StickBot with a couple of 555 timer circuits to allow it to roam freely and untethered. It was a lot of fun to build, and even though it’s not the fastest walker or the simplest design, it…
Here’s a small, inexpensive, modular, and easy-to-customize motor controller I’m working on that incorporates the Modern Device RBBB ($13), and Pololu’s TB6612FNG Dual Motor Driver Carrier ($8.50). If I fry or want to retask the brain or the driver or…
Here’s a little SQL gymnastics used to parse and query against a predictably-formatted long text field. The challenge: We have a single text field that contains a list person_id-to-area mappings, and we need the query the database for a list…
The goal was to crawl on the cheap, and what’s cheaper than popsicle sticks craft sticks and fishing line? Next we’ll wire up a 555 circuit so it can roam untethered, but until then, here’s how to make one of your…
In celebration of Independence Day here in the United States of America, here’s a great 10-minute narrated animation that reviews how the nation got to where it is today. Read the instructions, click the X, then click Play. Videos…