[Kc7fys] came up with a this simple battery level indicator. It uses a single LED to display a battery's voltage; if the voltage exceeds 12V, it glows green. If it is below 11V, the LED glows red. Anything in between generates an orange glow. The meter is built around an LM358 chip per this schematic, but his actual build looks pretty sloppy because of the dead-bug assembly (check out NASA's pretty version). Nonetheless, it works, so clean it up and build one if you want to put it (or your batteries) to the test.

Hardware modding can take you to some strange places: sometimes, you think of really useful improvements to your most practical devices. Other times, you turn a cup of tea into a theremin. This is true at least for [Kyle McDonald], who immersed the L/R leads of an 1/8" cable in a cup of tea, and connected it to a computer running Max/MSP with a special patch. The result is a working, miniature theremin you can drink after you're done playing. This process should work with any liquid, so feel free to use beer, cola, water, or anything you think will taste better after you've run a small charge through it.

[via Matrixsynth]

If you asked [David Phipps] whether he prefers Monomes or traditional keyboards, he might ask you "why not have both?" We don't presume to speak for him, but that's what we think he'd say based on his Monome-keyboard combination, which puts a Monome right in the keyboard's console, giving the user the best of both worlds.

[Phipps] calls his device The Peaceblaster (also the name of his album), and it is constructed from a 5-octave Fatar keybed, MKE electronic components, and a Doepfer PKE for the faders and knobs. Everything is available via USB and MIDI out. The project is as yet unfinished, and he hopes to fit a mac mini into the works. If he succeeds, this will be one of the most elegant, powerful and fun keyboards we've seen in quite some time.

Mark Fiore's Snuggly the Security Bear's latest cartoon explains the wonders of constitutional compromise and how it helps prevent terrorism through domestic spying.

Related: Judge: FISA trumps state secrets, binds executive branch

[via EFF]

If you're anything like us, you have a closet full of old electronics, some broken, some obsolete. You can stop using those as paperweights with the help of this guide that shows you how to recycle and reuse PCB components.

The first step of the process is finding electronics you don't mind taking apart. Next place the PCB you'll be stripping in a vice, with the components facing away from you and the solder side facing towards you. Grip the component you want with a pair of pliers, and apply a hot soldering iron to the solder that is holding the component. The solder will melt and allow you to safely and cleanly remove the component.

This process can be applied to virtually any component on an PCB, and the author of the guide, [Patented], got a lot of components this way, including resistors, capacitors, switches, audio jacks, and much more. Don't forget to toss any free-floating metal or plastic parts in the recycle bin when you're done. You can feel good about the fact that nothing was wasted, you found parts for your next project, and you cleared out some space.

A short while back, [Chris Anderson] released an Arduino based autopilot. It rings in fairly cheap and being open source, you can tweak away. To add more functionality, he's releasing a dual core version. Thanks to the second processor, it no longer requires an external hardware co-pilot. It uses an on-board GPS and features an ATtiny based fail safe. It's still under development, but he's made the design files available.

We love beer and we love robots, so guessing how we feel about this robotic bartender should be a no-brainer. Known as Mr. Asahi, the robot opens bottles and pours beer while taking your orders with aplomb and a jovial British accent. It also has a customized lazy susan with slots for bottles and notches for the robot's hand to grasp.

Amazingly, this is not Asahi's first beer pouring robot. That one requires you to do most of the leg work, though, so this one is a marked improvement. Best of all, it won't ignore you when a person more attractive than you comes into the bar, and it won't snub you for leaving a lousy tip. We now fear alcohol fueled robot rampages... they get more human every day. Video after the break.

So here's the situation: you have an audio device, maybe a boombox, perhaps one you built yourself, but it has no VU meter. No problem; building a VU meter is easy with these instructions from [Joe].

You'll need either an LM3915 or LM3916 chip, a couple of bread boards, two audio jacks, ten LEDs, and a few other components. Wire them all together per the schematic, then plug an audio source into the input jack. You can plug your speakers or output device into the output jack, and you're done. Keep in mind that LM3916s switch negative, so positive to positive wiring from LEDs to the bread board will be necessary. The wiring on [Joe]'s version is a bit convoluted, but it can be cleaned up on yours if you take the time. Video embedded below.

Nice try, Fujitaka. They manufacture cigarette vending machines in Japan, and were all set to roll out a new system of age verification cameras on their machines, which would scan the face of the buyer to look for sagging skin, wrinkles, age spots, and other signs of legal smoking age. The system is easily circumvented, however: people with a photo of an older person clipped from a magazine can fool the machine by simply showing the photo instead of their own faces.

Another aspect to Japan's cigarette control is the Taspo card, which is an age verified ID issued to smokers of legal age or older (20 years old is the legal age in Japan). Taspo cards are required for over the counter purchases, and the majority of vending machines require them as well. Relatively few machines are outfitted with face recognition systems, but many more are set to ship in the coming months. Fujitaka claims they are working on a solution by improving the face recognition software, but we think it would be a lot easier to simply check the background of the image. Since the camera is static and always pointed in one direction, the portraits it captures should always have the same background. Someone please tell Fujitaka we just saved them a boatload of R&D money... until Guy Fawkes masks become more popular.

We like clever work bench accessories; especially the kind that make our projects that much easier. [rstraugh] put up his version of the ubiquitous helping hands: thirdhand++. The arms are made from modular coolant tubing that's made for machine tools. With the basic arms in place, he created several attachments - like this PCB holder, a LCD holder, the usual alligator clips and even an oscilloscope probe holder.

Silverleaf Medical products has created an electric wound dressing that staves off infection by killing microbes in an open wound and preventing other germs from getting in.

They call it the CMB Antimicrobial Wound Dressing, and it is made of polyester fabric woven with a proprietary material called Prosit. When the bandage is moistened, the Prosit generates a low voltage, killing germs in the wound. One of these bandages can be worn for 3 days at a time, and their clinical trials indicate that they are highly effective in treating infected wounds. Take a look at their brochure (PDF file) for some informative and stomach-turning before and after photos.

[via Medgadget]

The guys (and gals) over at the NYCResistor definitely know how to have a good time. They decided to roast some marshmallows with a Jacobs Ladder. Mmmm. There's nothing like fresh 15,000 volt roasted.

The people at Brilldea have come up with LED Painter, a 16-channel RGB LED controller capable of controlling up to 48 independent LEDs. It uses a Texas Instrument TLC5940 to control the LEDs and can be connected to more LED Painter boards, creating a large array of RGB lights. The TLC5940 itself has been modified to make connecting independent LEDs easier.

The team strung together nine of these along with a Propeller-based controller called a Prop Blade and fitted the lights into three windows with semi-opaque glass to create a display of dancing randomized RGB lights. If all the dancing lights have inspired you, the TLC5940s are fairly inexpensive, but you'll need both through-hole devices and some SMT components to get if off the ground.

Flickr member and owner of awesome stuff [Firegroove] brought us a teardown of a Roland TR-909 drum machine before, and now he brings us a new photoset of a TB-303 synth teardown. The machines comprise two thirds of the holy trinity of 80's electronic music machines, so look after the break for more photos.