Wyvern quadcopter

[William Etter] and his classmates built a quadcopter as a class project. We love the details of these builds and they came through with some thorough documentation. Some highlights that we enjoyed were reading about ABS body design and construction, their analysis of two versus three blade propellers, and their breadboarded control mechanism. You can see their success in the most recent post, but we all know that trial and error plays a role in these builds so we’re glad they’ve shared a collection of crashes with us.

Can’t get enough of this four-rotor action? Check out this project of a similar design.

CPU As A Heat Sink

We’ve noticed that wireless routers pump out a bunch of heat. [Jernej Kranjec] wanted to make sure that he didn’t fry it once he started adding more load to his router using OpenWRT. What he came up with is the idea of using an old CPU as a passive heat sink. He applied a bit of thermal paste to the center and some super glue to the corners. You can see the finished product is an old AMD chip adhered “dead bug” style to the stock processor. We’d bet it’s not very efficient compared to an aluminum or copper heat sink, but it normally would have no help in shedding those extra degrees.

Chumby One Becomes A 3g Router

[bunnie] has taken a few moments to show us how to turn our Chumby One into a 3g router. As it turns out, there is an easter egg that allows it to communicate with certain models of 3g dongles. There’s no GUI for this trick, so you’ll be doing most of your configuration via SSH. That shouldn’t be a problem for this crowd though. The Chumby One just got a lot more appealing.

RF Transmission In The 9 KHz Band

[W1VLF] is on a quest to communicate over long distances with a 9 kilohertz transmitter. He built this giant coil with that in mind. A round concrete form was used as a base and wound with magnet wire by hand. We’d recommend building an automated winding device, but this method seems to have worked. Operating at 50 Watts on the air-core coil at 8.97 KHz he was able to pick up the signal at a distance of 5 kilometers. It’s not breaking any overall distance or portability records, but on a project like this the quest is where the fun is at.

[Thanks Drone]

WiFi And Bluetooth Sniffing Rifle

[.ronin] built an all-in-one WiFi and Bluetooth sniffer. He used a Nerf rifle as a base and added two Pringles cantennas, a tablet PC, and other various bits to tie it all together. Now he wanders the streets, explaining the device to bewildered passersby. After showing the device at CarolinaCon 2010 (here’s a PDF of his presentation) he stopped by the mall nibbled about 250 Bluetooth devices using SpoofTooph. The software is running on a Fujitsu u810 tablet and he’s making good use of Backtrack 4 during his wireless adventures.

Infrared Transmission Decoding

Alright class, quiet down and open your books to the chapter on Manchester Encoding. [Brian J Hoskins] did just that when building this RC5 decoder. This protocol is commonly used in television remote controls. You use them on a daily basis, don’t you think it’s time you understood what’s going on? Check out his writeup and learn the dark art of invisible light communication. Or just skip the learning and follow our how-to.

[Thanks Tim]

All About VLF Radio

If you’re interested in learning about Very Low Frequency communications take a look at what Larry has to offer on his site. He’s put together a guide to VLF receivers that is short enough to read and clear enough to understand with rudimentary knowledge of circuits. He builds a simple receiver as a working example and a high-powered transmitter that can put out over 2600 watts. Let’s face it, radio operators were the original electronic hackers. Get back to our roots and learn the ways of the transistor.

[Thanks Buddy]