Sanguinololu 1.3a Soldering Notes
A couple of people have noticed this, so I thought I’d write it up. There’s nothing wrong — it’s just something to be aware of if you’re soldering up a Sanguinololu 1.3a PCB. If you look closely at the circuit…
Category Odds & Ends
Mouser Electronics Shipping Costs and Turn-Around Time
The shipping “estimator” at Mouser.com is a little vague, so I thought I’d post the results of a recent order. In general, you’re not going to know the shipping cost or the weight of your order until after it’s shipped.…
Repraps for Education
As an active member of the #reprap community on IRC, I’ve started to realize that there are many others that share the common interest of getting 3D printing technology into schools, and so we’ve started a Google group to facilitate…
My $300 Prusa Mendel Build
I’ve set out to build a Prusa Mendel for $300. So far I think I’m doing pretty well. The top part is what I’ve already picked up, and the bottom part is what I have yet to purchase — that’s…
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…
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…