Hack a Day shirts at Defcon


We’ve printed [John Keppel]‘s winning t-shirt design. They’ll be available for purchase in the vendor area at Defcon. If you’re at the con, pick one up because we don’t have any plans yet to distribute them online. We will have a small number of women’s tank tops as well. See you there!

Sewer clog alert system


[miketysklar] noticed that a local business was having trouble with their sewage lines. People kept flushing tampons down toilets and it ended up clogging the pump. They had already installed a set of lights and horns to go off when it clogged, but they were hoping for SMS capability so they would know wherever they were. The new system piggybacks off the flashing lights by powering an XBee when they are activated. The signal it sends is recieved by another XBee attached to a computer running a python script. The script then sends a SMS via email to the poor fellow who has to fix it.

Related: Wireless Bootloading

Scanner sensor multi touch

[Kyle McDonald] had a Visioneer XP 100 portable scanner laying around, so he started trying to come up with alternative uses for it. In the video above, we can see a multitouch setup rigged together using Openframeworks in Ubuntu. As you can see in the video, there’s some considerable lag. That is due to the 250-500 ms of buffering built into the scanner. It does have nice resolution; 10k pixels wide at 60 fps, so it has to be useful for something (aside from scanning). Anyone got any ideas? He says if the field of view was wider, he’d use it on a river bed to watch fish.

Stereo Guitar


[Megatronix] wrote in to show us this pretty crazy guitar mod. He has re wired the pickups to make the guitar a “Stereo Guitar“. Generally, the two pickup locations on a guitar are there to provide tonal variation. You can adjust the influence of each to get the sound you want. [Megatronix] decided to re wire the setup so that one is the left channel and one is the right. Thus providing actual stereo sound from his guitar. This will limit his tonal variation considerably, but should at least serve as a proof of concept. We really want to hear a recording of it in action though.

Nokia schematics via Shenzhen


The silicon hacker behind the Chumby, [bunnie huang], was browsing through the Mobile Phone Megamarket in Shenzhen, China and stumbled upon an unusual repair book. It turns out the book had the schematics to hundreds of Nokia phones. It’s hard to tell if they are legitimate, but the amount of information makes them seem so. [bunnie] claims that the book is a learning experience because it shows how some sub-circuits are implemented. Also, it can be a good reference for sourcing parts. Since Nokia buys millions of each component, the supply of parts they use are stable. There are also editions for other brands, such as Motorola and Samsung.

Doorway subwoofer


We’ve seen some crazy speaker builds in the past (massive folded horns for example). [DiscoJones] wanted to build a set of speakers that could reach very low frequencies and be very efficient. Instead of constructing a large box, he built a baffle that could be placed in a doorway and use the blocked off room as an enclosure. It has eight 12inch subwoofers, eight midrange drivers, and four tweeters. The speakers are fairly cheap and he built a simple crossover to help them work a little better together. The goal was always deep bass though, so don’t expect very high fidelity from a setup like this.

Thin client as robot platform


[Extra Ketchup] has a couple Neoware thin clients and thought they would make a good robotics platform. It’s a Geode based board that came with Windows CE. He built a small Gentoo system to fit on the 130MB solid state drive. He likes the idea of using it as a platform because the board has serial, parallel, and USB support. The best part is shown above; it can run off of just 4 AA’s.