McMaster-Carr Shipping Costs
It’s not easy to find concrete examples of shipping costs for McMaster-Carr online, and they don’t tell you what an order is going to cost to ship until after it’s already shipped — and that can be a little scary…
Category Odds & Ends
DIY 12-Channel Bidirectional Logic Level Shifter
Here’s a 12-channel bidirectional logic level shifter with a 3.3V power regulator that I designed so I could easily interface 5V circuits with cool 3.3V widgets like the ADXL345 accelerometer, the NRF24L01+ wireless transceiver, and the Nokia 5110 84×48 LCD. For the…
Fun With Reuleaux Triangles
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…
Arduino-compatible GI-SP0256-AL2 Speech Synthesizer
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…
StickBot V2.0 – Untethered!
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…
StickBot: A Simple 6-Legged Walker
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…
Convert a Computer Power Supply into a Benchtop Supply
Here’s a great video from Phil Levchenko over at Jumper One that explains how to convert a computer ATX power supply into a bench-top power supply. I’ve had an older ATX supply by my desk here for the past couple…
Kilburn Highest Factor Routine in C#
To mark the 63rd anniversary of the first stored computer program to run (June 21), I rewrote the original code in C# last night, both using the original algorithm (that was never intended to be efficient) and using a more…
A Fox Family Came To Visit
Here are a few pictures of a gray fox and four pups that have been hanging out in back recently. The pups were a lot of fun to watch, and they stayed for an hour at least. They were *very* active…
DIY $3 Scrap Wood PCB Clamp
I’m still not fully convinced of the wisdom of a wooden soldering station clamp/vise, but it’s been serving me well nonetheless. It’s my DIY PanaVise! Why buy something if you can make it yourself, right? 🙂 The frame is made…