Large Magnets Spark On Halloween, Who Knew?

October 31, 2010 by Jakob Griffith 28 Comments

This overly large magnet certainly completes the mad scientist look (for an even crazier look, take a jar of water with red food coloring and place in one large cauliflower, instant brain in a jar).

The base of the magnet is painted foam cut with a makeshift hot-knife; to get the magnet sparking [Macegr] laser etched acrylic with a fractal pattern and embedded LEDs in the ends of the acrylic. An Arduino handles the flashing LEDs and also produces a 60Hz PWM pulse for the spark’s hum. The end result is satisfyingly mad, and while practicing your evil ominous laugh catch a video of the magnet after the jump.

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Beginner Concepts: Electronics Basics From The Giz

October 30, 2010 by Mike Szczys 7 Comments

Gizmodo University is open for business. This free educational series aims to educate about the basics of electronic theory. No prerequisite knowledge needed and they’re starting from the ground level. First lesson? Resistors! From there they’ve posted about voltage dividers, series/parallel circuits, Ohm’s law, and how to calculate a resistor value for an LED.

This is a great way to get the base knowledge that you need to start hacking like an EE. These are concepts that we assume you have already mastered if you’re following along with our AVR Programming series. We’re hard at work on part three but that’s still a little ways off. You’ve got time to do a review a GizU and reread our favorite book on electronic theory.

This Is A Peer-to-peer Filesharing Network

October 30, 2010 by Mike Szczys 116 Comments

[Aram Bartholl] is building his own filesharing network that screws those fat cats who want to control your freedom. He’s added file cache devices throughout NYC (five so far but more to come) that are anonymous and free to use. Upload what you want, download what you want. They’re completely offline which means monitoring who’s doing what gets a lot harder and quite possibly requires a warrant from a Judge (we’re obviously not legal experts, your mileage may vary).

As for the slew of comments that are sure to point out the dangers of malicious USB device; We think everyone knows they’re taking on some risk when connecting to a USB plug protruding from a brick wall.

[Thanks Neckbeard]

Hacking: A Disobedient Act That Drives Change

October 28, 2010 by Mike Szczys 16 Comments

[Adam Dachis] published an essay a couple of days ago called Why We Hack. In it he discusses the outlook that hacking, on all of its various levels, is a simple form of disobedience. We have to agree with him. Manufacturers would like you to think that voiding the warranty is as good as smashing the product to bits. But we all know that if you can’t crack it open you don’t really own it. [Adam] says we can sit around and complain about it, or we can do better. So crack it open, dump the firmware, and make it do your bidding.

If you haven’t already seen it, you should also go back and watch [Corey Doctorow’s] keynote address from Toorcon 8. He discusses freedom of information and hits especially hard on End User License Agreements (EULA) and the ills they cause. We’ve never seen someone hit the target quite as well as he does in this fantastic speech.

Artisans Asylum Takes On The Machine

October 28, 2010 by Jakob Griffith 6 Comments

You’ll probably lose your appetite after watching part one and part two of Artisans Asylum as they Take on the Machine. Based around the Wallace and Gromit “automated” set of contraptions, the team from Boston set out to make their own breakfast machine. Of course, with only three weeks to work it didn’t exactly turn out as planned. They certainly had some good ideas though, and we were amazingly impressed at their egg cracking machine. But in the end, we wouldn’t want to be first in line for a plate of breakfast. Next is the final team, The Transistor, who will be making a live action zombie video game.

[Thanks Deven]

Power Supplies And Transformers; A Learning Experience

October 27, 2010 by Mike Szczys 38 Comments

[Ladyada] is working on a tutorial series covering power supplies. If you’ve ever built an electronic project you’ve used some type of power supply but we think that most people have no idea how you get from mains power to the DC voltages that most small projects use. So if you want to learn, get started with the first installment which covers AC/DC converters based on a transformer like the one seen above.

These transformers are inside the heavy and hot wall-wart plugs that come with many electronics. We used one along with a breadboard power supply when building the pumpkin LED matrix. They use a pair of coils to step down the voltage to a much smaller level. From there it’s a matter of rectifying the AC into DC power, which she talks about in an easy to follow discussion.

We understand this type of converter quite well but we’re a bit foggy on switch-mode AC/DC converters that don’t use a transformer. They’re much better because you don’t have to build a regulator into the target project like you do with wall-warts. Can’t wait until she gets to that part of the series!

Ethernet Connection Using Capacitive Coupling

October 26, 2010 by Mike Szczys 26 Comments

Wanting to save space and weight on his project build [Florin] set out to find a way to add Ethernet connectivity without the magnetics. His ill-advised first try involved directly coupling two switches, frying both in the process. After some research he found that Ethernet hardware manufacturers have considered the need for devices without the magnetics and there are several application notes available on the subject. [Florin] followed the information that Realtek has for their devices and learned that they can be couple capacitively. After depopulating the magnetics from a second pair of switches he wired up some resistor-capacitor networks on a breadboard and got the connecting to work.