I watch a few documentaries a week, but it's rare for me to come across a series that I need to take notes on to keep up with. The first season of the BBC series "Connections" is one of those. It will blow your mind. James Burke walks us through the history of innovation from a touch stone (used to test the purity gold) right up to the atomic bomb, and explains how these two distant inventions are related. If you can see through the 1970s disco outfits and smoking on airplanes, you will be shocked that documentaries this good were being made 30 years ago.
The tirolessa sprayer is a simple tool that makes stucco work a blast. I have used the tirolessa to quickly cover my fence, battery dome, and front gates with an inexpensive cement plaster. Spraying makes the plasters stick better due the impact effect and saves a good deal of time compared to trowling by hand. The setup is nothing more than a 60 gallon air compressor, some air hose, a wheel barrel and a tirolessa sprayer, which actually directs the plaster. The air compressor provides enough pressure to shoot heavy mortars a few feet by squeezing a trigger on the sprayer handle. Using it is similar to using a can of spray paint. A commercial shotcrete, blastcrete or gunite setup would cost tens of thousands of dollars, but this setup is perfect for the DIYer. Check out the photo gallery to see some of my tirolessa projects, and read on for more about my setup and to see a video of it in action.
All batteries need love and the BC-900 is a great way to show that you care. I'm constantly charging for my five digital door locks, flashlights, GPS and cordless mice. This charger has been one of my favorite devices not only for keeping my gadgets going, but for prolonging the life of my rechargeable AAs as well. It sports a display and charge-control modes for each battery. Find out more about what this device can teach you about your batteries after the jump.
On any given day you can find a miniature multimeter in my pocket. These devices are the equivalent of a Leatherman for electronic enthusiasts. (The Leatherman would be in my other pocket.) Most of the time, I want to check the voltage of a deep-cycle battery in my electric-vehicle or troubleshoot a problem with a solar photovoltaic system. But multimeters do things like current measuring, resistance and continuity, which make them handy for solving problems ranging from home wiring to electronics repair. (For more on what do do with one, check out Ladyada's multimeter tutorial on adafruit.com). I've used a number of "portable" units over the years, and while many are anything but, one jumps out as my solid favorite. Here's my take on a few popular units.
Let's say you have a problem that can be solved with some electronics and maybe even a microcontroller. You gather up your parts and prove the idea on a breadboard, a sort of blank canvas for prototyping projects. Then what? A common solution is to solder everything to a blank perforated circuit board, but that still leaves you with a fragile mess of wires that looks like a disaster and takes a long time to assemble. The better idea: get a circuit board professionally printed. Too spendy? Think again. I've had about 10 different boards printed for all sorts of projects ranging from a trampoline that shoots fireballs to much less complicated boards that spells text on my bicycle wheels. These circuits are still working great fours years later and didn't break my wallet. Follow the jump to see my tips for getting professional boards without breaking your wallet.
Google is reported to have spent millions of dollars on its Street View project. Roy Ragsdale, a student at West Point, has done a pretty nice job of putting together a portable panorama camera setup that includes GPS and Google Earth file output for under $300, using exclusively open source tools.
I love rebar. It's most often used in concrete as a reinforcement, but it has a ton of uses. I've made a fence, a shed, and my future dome home armatures all from rebar. And since it's often made locally from old cars, it's relatively planet-friendly, too, and not very expensive. A 20-foot-long, 3/8-inch thick stick normally costs me about $4. I've purchased more than three tons of the stuff from a metal plant near the El Paso border, about 100 miles from my home.
Without any sort of approval from my girlfriend, I bought a 1984 diesel Mercedes-Benz through eBay. Two years later, the vehicle has provided me with nearly 10,000 miles of service on waste vegetable oil (WVO). The fuel may technically be free, but it has not come without a price. Here's how I converted my car, affectionately known as "Chance," to a veggie-oil roadster, and some of the hard-learned lessons I picked up along the way.
Can pulsing 36 high-powered LEDs invoke sea-sickness? Adafruit have put together a $250 non-lethal weapon modeled after a 1 million dollar government project. The source code, schematic, and circuit board files are available. Included is a helpful video describing how she learned about these weapons and tests her own unit out on her boyfriend.
Arduino is a great microncontroller package for entry-level electronics tinkerers, but once you've got your sea legs, cheaper DIY microcontrollers used to build anything from grow-lights to irrigation systems are what you might reach for next
The Arduino platform is doing something amazing: bringing hardware development to the masses. It's a sweet little system, with a built-in hardware programmer, simplified programming language, and lively user base that offers plenty of sample code and assistance in the online forums. While this fully assembled solution is a good way to get your feet wet, there are a lot of good reasons to just buy an off-the-shelf processor, make your own circuit board and write in a low level language like C. It can be cheaper, quicker and easier to debug. Here, check out some of the projects I've made and how I pay for my hobby, as well as my hardware setup.