Month: October 2012

Raspberry Pi Foundation Looks At Counterfeit Apple Power Supplies

October 10, 2012 by 42 Comments

The Raspberry Pi foundation is in a somewhat unique position. They always test the units that get returned to them in hopes that they can improve the design. They often request that the power supply also be sent back with the RPi unit, as we know the board will not work well if the PSU can’t source enough current. And so they’ve been able to get a look at several counterfeit iPhone chargers. This is not one of the recommended ways to power the RPi, but their ability to collect failed hardware means that they have identified three different fakes on the market.

Seen here is a genuine Apple product on the left. The others are fake, with the easiest way of spotting them being the shiny chrome plug connectors. The genuine part has a matte finish on the connectors. There is also a difference in the chamfering, and even a variation on the orientation of the USB port on some of them. Unfortunately we don’t get a look inside, which is what we really wanted. But you can see in the video after the break that weighing the adapter will also give it away as a fake, showing that the components within probably vary quite a bit. This reminds us of some other fake PSUs that have been exposed.

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Giving The Rigol DS1052E ‘scope A Spectrum Analyzer

October 10, 2012 by 16 Comments

Like a lot of hardware tinkerers, [dexter2048] has a Rigol DS1052E oscilloscope sitting on his bench. One day when trying to coax some information out of the FFT setting, [dexter] threw his hands up in frustration and decided to write a file viewer with FFT spectrum analysis. The resulting viewer gives this very capable and inexpensive oscilloscope a spectrum analyzer.

[dexter2048]’s app is able to capture signals from 0 Hz to 500 MHz and demonstrated this fact by sticking a piece of wire into one of the Rigol’s inputs. The resulting waveform is then sent to a computer where [dexter] got a nice picture of the radio spectrum between 82MHz and 114MHz. In his graph, you can clearly see the FM radio stations that can be picked up in [dexter]’s lab.

This small modification to the Rigol DS1052E oscilloscope it the latest in a long line of hacks that give this wonderful, inexpensive scope double the bandwidth, data collection via Python, and even a homebrew version of Pong. Anything that provides new functionality for old gear is great news to us, and we look forward to many, many more 1052E hacks in the future.

Tip ‘o the hat to [Murlidhar] for sending this in.

Papercraft Flash Reflector

October 10, 2012 by 13 Comments

We never use the flash on our point-and-shoot. It has a way of washing out every image we take. But [Joey] has a different solution to the problem. He shows us how to make a papercraft flash reflector that will still light up your subject without washing out everything in the foreground.

[Joey] is perfectly aware that at first glance it would seem you need to have a reflective forehead for this to work. But the reflector is actually set up to aim the flash toward the ceiling. Since most ceilings are white this will reflect the light back into the room, dispersing it at the same time. His write-up includes a link to a PDF of the pattern. After cutting it out, one side is coated in black electrical tape, the other is left white to reflect the light. The design includes a tab that slides into the hot shoe of his Nikon DSLR to position it in front of the pop-up flash.

Putting Guitar Pedals In A Web Page

October 10, 2012 by 13 Comments

Only half of playing guitar – according to a few musician friends of mine – is moving your fingers up and down a fretboard and banging out some chords. The other half is the artistry of mastering your tone, usually through amp settings and stomp boxes.

Effects pedals – little boxes of electronics that go between the guitar and amp – are able to amplify and distort a guitar’s output, add reverb and delay, and even filter the tone via a wha or envelope pedal. These pedals can be simulated in software, but we can’t believe that they can now be emulated completely in JavaScript.

Pedalboard.js is a project put together by [dashersw], and aims to put a slew of pedals ‘in the cloud’ and turn editing and effects board as easy as building a web page.

The project is built around Webkit’s W3C audio API, allowing this virtual pedal board to work in Chrome, Safari, and other Webkit-enabled browsers. Pedals are programmed as nodes, each configurable to have and input, output, or analyzer that is able to modify the gain, wave shape, or filter of anything received by the line in on your computer.

Thee is a small demo of Pedalboard.js available here with a pre-recorded guitar track feeding into a few stomp boxes. It’s a pretty cool idea if you’d like to play around with a few guitar effect, but we can’t wait to see this bit of JavaScript implemented by effects pedal manufacturers allowing us to try before we buy.

Desktop Mill Built As A High School Project

October 10, 2012 by 43 Comments

This desktop mill would be impressive coming from anyone, but we’re really excited that it was made as a high school project. [Praneet Narayan] built it during his design and technology class. As his build log shows, he worked with a range of different tools to make sure he had a rock-solid platform on which to mount the motors and cutting head.

The uprights of the frame are made from two steel plates. After hacking them to rough shape with a plasma cutter he finished the edges with a mill. The two parts were then tack welded together so that the mounting holes could be drilled in one step, ensuring alignment between the two sides. The rest of the frame parts are built from extruded rails but he did machine a set of mounting plates to pull it all together. You can see the finished machine milling a message in MDF in the clip after the break.

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Using Arduino Shields With The Raspi

October 10, 2012 by 12 Comments

With hundreds of Arduino shields available for any imaginable application, it’s a shame they can’t be used with the Raspberry Pi. Breaking out the Raspi GPIO pins to Arduino-compatible headers would allow makers and tinkerers to reuse their shields with a far more capable computing platform.

The folks over at Cooking Hacks realized a Raspi to Arduino shield bridge would be an awesome device, so they made their own, complete with a software library that allows you to port your Arduino code directly to the Raspberry Pi.

There are a few limitations with the Raspberry Pi’s GPIO headers; the Raspi doesn’t have analog inputs, so the Cooking Hacks team added an 8-channel ADC. Along with analog inputs and the headers required to pop a shield on the board, there’s also a socket for an XBee module.

The software library contains most of the general Arduino functions such as digitalWrite() and digitalRead(). There Serial, Wire, and SPI libraries are also implemented, allowing any device that communicates through UART, I2C, or SPI to talk directly to the Raspberry Pi.

While the Raspi Arduino bridge doesn’t allow for PWM in the same capacity as an Arduino, you’re always welcome to whip up a servo or LED shield for this neat little adapter.

Free Software Foundation Certifies Hardware That Respects Your Freedom

October 10, 2012 by 32 Comments

The Free Sofware Foundation, the very same organization responsible for the GNU General Public License and open source advocacy on the part of the Free Software stalwart [Richard Stallman], has certified its first piece of hardware as Respecting Your Freedom.

This new certification goes far beyond the goals of Open Source Hardware. In addition to providing documentation, schematics, and design files, hardware certified as Respecting Your Freedom must meet much more stringent requirements.

Of course, all software used with RYF hardware must be Free Software, but the certification also carries with it a few more requirements. The source and CAD files must be provided, it must use formats unencumbered by closed licenses, and the hardware must not spy on the user.

The honor of the first RYF-certified piece of hardware goes to, of course, a 3D printer. It’s the AO-100 printer developed and sold by Aleph Objects, Inc., a.k.a. Lulzbot out of Colorado.

With so many Open Source Hardware projects coming down the pipe, it’s great to see a somewhat more militant organization (that’s a good thing!) such as the Free Software Foundation provide a certification process for hardware projects. Keep in mind this isn’t a ‘certified once and forget about it’ proposition; the FSF is willing to provide a bounty to encourage the public to report violations of RYF certification. Anything to keep them honest, right?