[Dominik’s] daughter had an old toy piano that she loved, but when the batteries started to die down, it played awful tones and sounded generally out of tune. While this is likely something our circuit bending friends might be interested in, [Dominik] preferred when things sounded more cheery.
He considered simply replacing the batteries, but it seemed like a far better idea to do away with them altogether. he hunted around for a solution, and eventually found one at the local IKEA store. He grabbed a LJUSA hand-powered flashlight and disassembled it, saving the crank and circuitry.
He installed the crank on the back side of his daughter’s piano, and mounted the electronic bits inside the toy’s shell. The crank spins a brushless motor, generating an AC current which is rectified to DC before being stored in a capacitor. He says that a 30 second crank will play just a few tunes, which isn’t ideal, though it is better than frequently replacing batteries.
Although not everyone has the ability to make a hacked Pong game Like [Marcelo], even fewer have the ability or the creativity to come up with the elaborate hack that he did. The basic premise of his game is a version of pong played on a breadboard with a 8×8 matrix of LEDs. The controls are really what sets this hack apart. Instead of using a paddle controller or normal switches, small flashlights are used to control the on-screen (on-LED matrix) paddle. This is accomplished using a series of photoresistors and a PIC processor.
Innovative as this would be by itself, [Marcelo] decided to make a program in Flash to display the action on a computer. Communication is done serially, and C# is used to translate everything as Flash doesn’t natively work with a serial connection.
Another innovation is that there are two LEDs connected on either side powered via pulse width modulation. The lights get dimmer as one player is about to lose. Check out [Marcelo's] pong game after the break!
[Holzleim's] flashlight build is quite impressive. And the rise and fall of the hardware is quite a story. He designed it as a handheld light, relying on batteries to power a multitude of high-power LEDs inside.From the collection of four 5350 mAh lithium polymer cells he was able to achieve a peak power output that surpasses 500 Watts!
Projects that make use of these powerful LED modules have heat dissipation as a major design element. With this in mind, [Holzleim] used large bars of copper as a mounting surface for each group of modules. The size and thickness of these bars made it difficult to use traditional soldering techniques to affix the bodies of the modules so he ended up using a clothes iron to ramp up the temperature high enough to reflow the solder. Once mounted, most of the LEDs were paired with optics, including that Fresnel lens at the center, to help focus the light.
To keep the batteries topped off, [Holzleim] designed his own external charger which can run off of mains or from a car’s electrical system. Unfortunately he must not have included a way to monitor the battery temperature because one of the cells failed, causing a fire that burnt out the components inside the flashlight. Luckily his wife was home at the time and got the failing device outside where it didn’t cause more damage. We’ve linked to his posts regarding the charging system, the properly functioning light burning paper with its beam intensity, and his sad announcement about the fire after the break.
[Oneironaut] sent us another IR hack. This time it is a writeup on the best ways to create IR light sources from regular lights. Since normal flashlight bulbs emit a broad enough spectrum to include visible light and IR light, this basically comes down to filtering. [Oneironaut] explores different light sources and different materials in depth, along with great pictures to show his results. This is a great resource if you’re needing to do some night vision for cheap.
[Robbtoberfest] has earned our admiration with this crazy chainsaw powered spot light. It looks horribly dangerous, extremely inefficient, and woefully under engineered. We absolutely love it. This could be plucked from a video game or a movie and seems to be one UV bulb away from being the ultimate post apocalyptic zombie vampire Armageddon weapon. He has taken apart a chainsaw and attached it to a DC treadmill motor using a couple of bike sprockets and a chain. That DC motor then feeds a car headlight directly. As you can see in the video, when he cranks the gas, it shines pretty brightly. The unfinished nature of this is due to a deadline for a contest on instructables, so he plans on adding a protective cowl, some fancy paint work, and a voltage regulator down the road.
Building an LED flashlight is simple, right? Take a battery, connect it to an LED by way of a resistor. Alright wise guy, now make one that steps up the voltage for multiple LEDs and don’t use a boost-converter IC to do so.
[fede.tft] shares a flashlight built inside of a used glue stick case. It’s the perfect size for one AA battery (we’re always on the lookout for good battery cases), and a shape that we’re familiar with as a flashlight. The problem is that he wants two white LEDs but with just one AA cell he’s never going to have more that 1.5V available. He licked that problem, getting to 7.2V by designing his own step-up converter using one transistor, an inductor, and three passive components. To get the inductor he needs, a stock part is disassembled and rewound to suit. Maybe you just end up with a flashlight when all is said and done, but then again, the Sistine Chapel is just some paintings on a ceiling.
When [Neelandan]‘s cheap flashlight’s internal rechargeable battery died, he scrounged for a replacement. Ultimately, the brightness of the light suffered with his new battery, taken from an old cell phone since he had dropped the voltage a bit. Upon inspection he saw that he would have to swap the individual resistors for each lamp to get the desired brightness again. This wasn’t really acceptable as he would have to repeat the process if he used another re-purposed battery with different specs. Instead, he added a new circuit to supply constant brightness until the voltage drops below 2.7 volts. We love to see hardware resurrected, even if it is just a cheap LED flashlight.
Going camping? You’ll need an extra backpack to carry this flashlight along the way. On the business end you’ll find 500 five millimeter super-bright white LEDs, on the opposite end there’s ten times the number of controls you’d expect on a flashlight. At full power, the LED array pulls down 50 Watts, making us question the battery life of the unit. Check out the walk-through after the break. The LEDs are mounted on proto-board, making for some extreme point-to-point soldering. During the control demonstration there’s a background noise like a jet powering up, what’s that all about?
While this terrific torch brings a grin to our faces, we wonder if it wouldn’t do better as a vehicle mounted illuminator. Or if a microcontroller was tossed into the mix some creative code could make this a pretty powerful yet non-lethal weapon.
