Help Decipher The DEFCON Badge

August 6, 2015 by Mike Szczys 25 Comments

The 23rd DEFCON — the Western Hemisphere’s largest hacker conference — doesn’t start until tomorrow but Thursday has become the de facto start for regulars. [Brian] and I rolled into town this afternoon and are working on gathering as much information as possible about the badge challenge.

This year the badge is a 7″ vinyl record. Traditionally the badge alternates years of electronic badges and ones that aren’t. Spend your weekend pulling your hair our trying to solve the puzzles. Check out all the pictures and information (updated as we gather it) and work together collaboratively for a solution by requesting to join the crew on the Badge Hacking page.

Hackaday Breakfast on Sunday

If you’re in town Sunday morning, come nurse your hangover with [Brian], [Eric], and me. We’re headed to Va Bene Caffè at 10:30am on 8/9/15. It’s just across the street in the Cosmopolitan. Request to join this event and I’ll send you a reminder so you don’t forget. You can also hit me up on Twitter for a reminder. See you then (and don’t forget to bring hardware to show off if you have some!).

PS- The Hackaday WiFi Hat is in play. Anyone have the chops to hack it this year?

Keep Your Friends Close And Your Tools Closer With This Pegboard On Rollers

August 6, 2015 by George Graves 28 Comments

There’s nothing that adds more time to building or repairing something than having to walk back and forth to grab the right tool for the job. “Wait, was that a 15/16 inch socket I needed? Nope it’s a 3/4 inch! Rats!”

[Brad Justinen] shares his solution to the problem in this very simple, but well documented tutorial on Instructables. He welded up a metal A-frame, then simply added pegboard to the sides and casters to the bottom. Our first thought was if something like this could be made out of lumber for a bit more of a DIY approach, but if you’ve ever moved a tool box full of tools, you know how their weight really adds up fast. So perhaps it might be best to bribe your welder-owning friend with a 12 pack of his or her favorite adult beverage.

If you haven’t used pegboard for organizing tools, it really can be a wonderful solution to getting organized. Pegboard has many more uses as well. Check out this pegboard cable organizer, or this modular soldering platform.

$40 Antenna Analyzer With Arduino And AD9850

August 6, 2015 by Al Williams 39 Comments

If you are a hacker, you might consider ham radio operators as innovative. Most people, however, just see them as cheap. So it is no surprise that hams like [jmharvey] will build an antenna analyzer from a DDS module and an Arduino instead of dropping a few hundred dollars on a commercial unit. As he points out, you probably only need an analyzer for a day or two while you set up an antenna. Unless you are a big time antenna builder, the unit will then sit idle on the shelf (or will wind up on loan to hams even cheaper than you are).

The design is rooted in another proven design, but changed to take advantage of parts he happened to have on hand. Although the build is on a universal circuit board, [jmharvey] used Eagle to lay out the circuit as though it were a PCB. Since placement can be important with an RF circuit, this isn’t a bad idea. It’s always easier to move stuff around on the screen than on the perf board.

Since this is a no frills, unit, you are expected to grab the output from the Arduino and manually put it in a spreadsheet to plot the results. There is another version of the Arduino code that drives an OLED screen, although you still need a PC to kick the process off. One interesting feature of the Arduino code is how it deals with the nonlinear nature of the diodes used in the circuit. After plotting the values with known loads, [jmharvey] broke the diode operation into three regions and used different equations for each region. Even so, he warns that readings higher than 1:1 VSWR are only accurate to 10% or 20% – still good enough for ham shack use.

If you want an antenna analyzer for $40 (or less, if you have a good stock of parts) this looks like a worthwhile project. If, however, you want to repurpose it to Rickroll your neighbor’s AM radio, you might want to go with the commercial unit.

Click past the break to see the analyzer in action.

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Hacking A Universal Assembler

August 6, 2015 by Al Williams 30 Comments

I have always laughed at people who keep multitools–those modern Swiss army knives–in their toolbox. To me, the whole premise of a multitool is that they keep me from going to the toolbox. If I’ve got time to go to the garage, I’m going to get the right tool for the job.

Not that I don’t like a good multitool. They are expedient and great to get a job done. That’s kind of the way I feel about axasm — a universal assembler I’ve been hacking together. To call it a cross assembler hack doesn’t do it justice. It is a huge and ugly hack, but it does get the job done. If I needed something serious, I’d go to the tool box and get a real assembler, but sometimes you just want to use what’s in your pocket.

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Quantum Mechanics In Your Processor: Quantum Computing

August 6, 2015 by Will Sweatman 54 Comments

Not long after [Hitler] took control of Germany, his party passed laws forbidding any persons of Jewish descent from holding academic positions in German Universities. This had the effect of running many of the world’s smartest people out of the country, including [Albert Einstein]. Einstein settled into his new home in Princeton, and began to seek out bright young mathematicians to work with, for he still had a bone to pick with [Niels Bohr] and his quantum theory. It wasn’t long until he ran into an American, [Nathan Rosen] and a Russian, [Boris Podolsky]. The trio would soon lay before the world a direct challenge that would strike at the very core of quantum theory’s definition of reality. And unlike the previous challenges, this one would not be so easily dismissed by [Bohr].

Need a bit of catching up? You can check out Complimentarity as well as Tunneling and Transistors but that is just some optional background for wrapping your head around Quantum Computing.

The EPR Argument

On May 4th, 1935, the New York Times published an article entitled “Einstein Attacks Quantum Theory”, which gave a non technical summary of the [Einstein-Podolsky-Rosen] paper. We shall do something similar.

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Visualizing RF Standing Waves

August 6, 2015 by Dan Maloney 14 Comments

Standing waves are one of those topics that lots of people have a working knowledge of, but few seem to really grasp. A Ham radio operator will tell you all about the standing wave ratio (SWR) of his antenna, and he may even have a meter in the shack to measure it. He’ll know that a 1.1 to 1 SWR is a good thing, but 2 to 1 is not so good. Ask him to explain exactly what a standing wave is, though, and chances are good that hands will be waved. But [Allen], a Ham also known as [W2AEW], has just released an excellent video explaining standing waves by measuring signals along an open transmission line.

To really understand standing waves, you’ve got to remember two things. First, waves of any kind will tend to be at least partially reflected when they experience a change in the impedance of the transmission medium. The classic example is an open circuit or short at the end of an RF transmission line, which will perfectly reflect an incoming RF signal back to its source. Second, waves that travel in the same medium overlap each other and their peaks and troughs can be summed. If two waves peak together, they reinforce each other; if a peak and a trough line up, they cancel each other out.

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Build A Baby Plasma Cutter–Right Now!

August 6, 2015 by Al Williams 43 Comments

What hacker doesn’t want a plasma cutter? Even if you aren’t MacGyver, you can probably build this one in a few minutes using things you have on hand. The catch? You probably can’t cut anything more than tin foil with it, and it is probably more a carbon-air arc gouger (which uses plasma) than a true plasma cutter. Still, as [Little Shop of Physics] shows on the video, it does a fine job of slicing right through foil.

If you are like us, you are back now after getting four 9V batteries, some tin foil, a pencil lead, and some clip leads and trying it. If you have more self-restraint than we do, you might want to think about what you are going to put the tin foil over. In the video, they used a laundry basket and a rubber band, but anything that keeps the foil suspended would do the trick.

Although it isn’t really a practical plasma cutter, we were thinking about strapping something like this to a 3D printer and cutting foil stencils. The jagged edges on the video are, hopefully, more from being operated by hand and less from the jagged mini-lightning bolt vaporizing the foil.

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