IR Air Conditioner Timer

October 10, 2009 by Caleb Kraft 20 Comments

installed (Custom)

[Tom] has an office job in China. His office is cooled by a small single room air conditioner. In an effort to make his office a little more comfortable, he built this IR timer unit. It cools his office down before he gets there so he doesn’t have to wait for it in the morning. He started by decoding the IR signal from the remote for the unit. He then built this ATiny13 based remote. He notes that the internal clock of this thing isn’t that accurate. power cycling it every day seems to help. It is also pretty cool that he built the unit to not only send the cooling code, but he can switch it to the heating code for the winter.

[thanks Mario]

TV-B-Gone-zilla! Rawr!

October 7, 2009 by Phil Burgess 34 Comments

tv-zilla

TV-B-Gone: antisocial nuisance or harmless prank? Whatever your feelings, there’s no denying this device has become a staple of the DIY hacking crowd, as evidenced by the countless derivatives since hatched. This latest mutation crushes them all.

[manekinen] from the Polish electronics blog Elektroda (“Electrode”) wasn’t satisfied with high-power TV-B-Gone designs using multiple 5mm infrared LEDs, so he created his own using a single one-Watt monster. The device is concealed in an ordinary flashlight casing, making it somewhat inconspicuous. A custom PCB containing an ultra-minimalist version of the TV-B-Gone circuitry sits just behind the reflector. The choice of reflectors determined maximum distance vs. coverage…they opted for distance. Specific figures aren’t given, but we estimate this thing could shut off televisions on Mars.

The original article (Polish or Google-ized English) includes construction photos and an archive (.rar) of project files including Eagle schematics and C source code.

Would it be totally irresponsible to mention there’s now a 3-Watt version of this LED? We’re just sayin’.

[thanks RicoElectrico]

Building An IR Receiver For The Popcorn Hour C-200

October 5, 2009 by Caleb Kraft 10 Comments

IR_module

[Linuxworks] has posted a writeup on how to build an IR module for the popcorn hour c-200. We weren’t familiar with the popcorn hour c-200, so we had to look it up. It seems to be a media center pc sort of thing. We’re not reviewing the unit itself, since we’ve never used one, so we’ll just get back to the mod. The device uses an RF remote, which some people didn’t like as much. Luckily it has an expansion port which can be utilized to get IR signals into the machine. [Linuxworks] has used a cheap IR sensor and a standard headphone plug. He notes that equipment passing power through these plugs should be turned off before plugging them in or removing them as they short momentarily during insertion.

Growing Algae With An Arduino

October 2, 2009 by Matt Schulz 58 Comments

algae_grow

We’ve seen automated grow boxes of all shapes and sizes, but all were for growing plants. [Jared] over at Inventgeek wanted to do something similar for his algae. He started off with an Arduino-based solution that allows the controlled pulse of LEDs connected to his standard bioreactor as a prototype. Once he determined his proof of concept worked, he began work on a design based on the Arduino Pro Mini that has more advanced features such as temperature monitoring and algae culture density monitoring via some fancy IR voodoo. The code is open source and the hardware is easily obtainable, all that remains is the desire to grow algae.

Passive Infrared (PIR) Sensor Tutorial

August 21, 2009 by Phil Burgess 18 Comments

pirsensor

[ladyada] has a freshly-published and amazingly thorough tutorial on passive infrared (PIR) motion sensors. Most often seen in security floodlights and automatic doors, in creative hands these sensors can be put to other uses—cat flaps, camera triggers and purely artistic applications—as you’ll see in several demo projects and videos. For the curious, the tutorial provides a good amount of background theory on how PIR sensors work, along with the associated fresnel lens optics. And for those who just want to get hacking, most PIR sensors (like the one above) come in a simple-to-interface module containing all the support hardware and providing a simple digital output; the article wraps up with one such example.

Hackit: Ideal Conference Badge?

August 11, 2009 by Eliot 28 Comments

In 2006, Defcon 14 premiered a unique electronic badge. All it did was blink, but it raised the bar for what was expected from a hacker conference badge. In 2007, they went from 2 LEDs to 95 in a scrolling marquee. Along with a POV mode, the badge had two capacitive switches to let the user edit the displayed text. Defcon 16’s badge featured an IR transmitter and receiver for transferring files from an SD card. It worked as a TV-B-Gone and had pads to access a USB bootloader. That was the same year that The Last Hope debuted their RFID tracking badges.

This year the official Defcon badge reacted to sound, but they were no longer the only game in town. Ninja Networks brought their 10 character party badges with a built in debugger. The Arduino compatible HackTheBadge 1.0 also made an appearance. With these new entrants into the field, we wondered what you’d want to see in your ideal badge. What badge would you want to see at next year’s Defcon? Leave you comments below and keep in mind that it should be an idea that is easy to cheaply mass produce.

UPDATED: Forgot to mention the Neighborcon 2 badge based on the GoodFET20.

[Photo: Ninja Networks]

Pet-squirting Waterwall

July 24, 2009 by Zach Banks 8 Comments

waterwall

Sometimes, pets need to be trained to stay away from certain things. Over at sump.org, his cats needed to be kept out of his room. He used their natural fear of water by creating the waterwall, a motion-sensing device that sprays water. The project is incredibly simple and uses very few components. It is based around an IR intrusion detector and a windshield washer pump. Although that worked well enough, he also hooked it up to his computer via the parallel port so that he could take pictures as the cats (or people) are sprayed. Although the project is old, it shows how few components are really needed to achieve this kind of behavior.

Related: Motion detecting cat toy

[thanks todd]