Building a glue stick flashlight

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.

Keep tabs on your car without OBD-II

[Steve] let us know about his MultiDisplay car monitoring system. Unlike traditional systems that rely on interfacing with the OBD-II protocol and existing car computer, the MultiDisplay uses an Arduino and custom shield with a combination of sensors; including temperatures, pressures, throttle, Boost, and etc. The data collected can then be displayed on a 20×4 LCD or streamed to a PC with visualization and event recording.

It’s nice to see half a years worth of work finally be complete and presented in such a clean and professional manner, keep up the good work [Steve]

Laser raygun boasts 300mW, hunts Klingons

laser-ray-gun

Phasers come with two settings: stun and kill. [Luke] took this seriously when he put two Blu-ray lasers into a toy raygun. He picked up the toy from Amazon for about twenty bucks and set to work.

The laser diodes are both pulled out of a 6x BD-R burner, which we think is a pretty expensive source to scavenge from. [Luke] removed the toy circuitry, reusing the trigger, top switch, and battery pack. The two diodes are mounted on a swiveling carriage which is turned 180 degrees to switch between the two diodes. A boost driver converts the 3v from the batteries up to 7v for the diodes.

This is a skillful conversion and [Luke] should be proud. Don’t miss the video after the break and if you’re thirsty for more take a look at the last hand held laser we featured.

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