Putting Laptop LCDs To Use With An FPGA

September 9, 2011 by Brian Benchoff 29 Comments

We’re always impressed with the number of laptop displays we’re able to pick out of the trash. Most of the time the computer is borked beyond repair so we end up with a lot of functional but unusable LCD panels. As a service to us all, [EiNSTeiN_] figured out how to control an LCD panel using a cheap homebrew FPGA board.

LCD panels don’t use a simple protocol like VGA for turning pixels on and off. Instead, the very high-speed LVDS is used. LVDS is beyond the capabilities of simple microprocessors, so [EiNSTeiN_] built himself a clone of an XuLA FPGA prototyping board and set to work. After figuring out the signal lines to the panel, [EiNSTeiN_] pored over the timing diagrams for the LVDS controller and the LCD panel. From the data sheets, he figured out data is usually sent to the panel at about 500 MHz. The homebrew FPGA board couldn’t manage that speed so [EiNSTeiN_] cut the FPGA clock in half.

While LCD’s 60 fps refresh rate was reduced to 30 fps, [EiNSTeiN_] says there’s only a little flicker. Not bad for something that could have easily been trashed.

Controlling Samplers And Sequencers With Multitouch

September 6, 2011 by Brian Benchoff 5 Comments

When we see artists like Daft Punk or Madeon working their magic in a live setting, we’re always impressed with their controllers. Sample-based artist use controllers like the Monome and Kaoss Pad a lot, but these devices are fairly expensive. Thankfully, we live in an age of multitouch displays, so [Graham Comerford] came up with his own multitouch controller that does just about anything.

The build is based on the Kivy framework and includes a Monome emulator, MIDI drum pads, mixer, and a whole bunch of other sliders and buttons. There’s no word on how [Graham]’s multitouch display was constructed, but if you’re looking to build your own gigantic audio control setup there’s a lot of info on building Microsoft Surface clones, adapting computer monitors, and spherical multitouch rigs.

We’re not sure if [Graham]’s virtual drum kit is velocity sensitive but even if it’s not, it’s an interesting bit of kit. Check out an earlier version of his setup after the break.

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High Voltage Hacks Finale: Do Not Try This Under Any Circumstances

August 28, 2011 by Brian Benchoff 31 Comments

Over the last two weeks, we’ve seen some pretty crazy and potentially dangerous stuff, like a stun glove and modern day alchemy. For our high voltage theme finale, we couldn’t pass up [Photonicinduction]’s YouTube channel.

Best known for his self-destructing washing machine (the source of this animated .gif), [Photonicinduction] is also the brainchild behind the hair dryer flame thrower and his homemade fifty thousand amp transformer.

While we do like his Not Safe For Work ammeter (yes, it really is NSFW), some of [Photonicinduction]’s videos – charging a car battery in 4 minutes, making a kettle boil without a heater element, pressurizing coconuts to over 200 psi, and exploding rabbits – are hilariously dangerous and should not be attempted by anyone.

We need to say you should not attempt to emulate [Photonicinduction]’s hijinks under any circumstances. Cleaning up a puddle of burning gasoline with a vacuum cleaner may sound like fun, but copying [Photonicinduction] will eventually get you killed. This man must know his stuff, because we’re honestly shocked he hasn’t exploded yet. The best way to enjoy three hundred thousand volts is probably grabbing a coffee and watching [Photonicinduction]’s YouTube channel.

Dev Board From An AVR Programmer

August 26, 2011 by Brian Benchoff 8 Comments

[jethomson] sent in a build he’s been working on that turns an inexpensive AVR programmer into a development board. The build is based on the very affordable USBasp programmer that’s based on an ATmega8. With hundreds of these boards available from China for less than a Hamilton, we’re wondering how soon it will be before we see these boards end up in other projects.

After fiddling with the AVR fuse settings, [jethomson] managed to burn some code to the microcontroller. After that, all that was required to upload software to the programmer is a bit of solder, a push button, and an external programmer. [jethomson] also managed to make this little AVR programmer compatible with the Arduino environment with a small addition to the boards.txt file.

[jethomson] included a few bits of software as an example – he ported the haunted USB cable and adapted the USB business card to print out, “All work and no play makes Jack a dull boy.” Nice work, and we can’t wait to see it in future projects.

High Voltage Hacks: A 1000 Watt Tube Amp

August 26, 2011 by Brian Benchoff 26 Comments

Normally when we hear of a Champ guitar amp, we think of a sweet-sounding rig that puts out 6 Watts through an 8-inch speaker. [John Chambers] of Champ Electronics wanted to build a true champion for the field of battle and came up with The Champ 1000 Watt Tube Amp, an amplifier that probably puts out enough heat to keep an igloo warm.

The amp is based on 807 valves. With some clever engineering [John] managed to coax 100 watts out of a pair of 807s, so the entire amp “only” requires 20 power tubes. The build log shows some pretty impressive examples of electrical prowess. We can’t recall the last time we featured a build with point-to-point wiring on tagboard, and [John]’s work is some of the best we’ve ever seen.

[John] has been working on this amp off and on for a few years now, but he should be wrapping up the build sometime soon. We haven’t seen this amp in action, but we imagine it would look something like this 36×10 monstrosity. Send us a message or post a comment if you can find a video and we’ll put it up.

Raspberry Pi Might Not Be Vaporware

August 26, 2011 by Brian Benchoff 73 Comments

When we first covered the Raspberry Pi, we secretly wondered if the project might become vaporware. It looks like the tiny, full-fledged computer might actually be produced with the announcement of alpha boards in the Raspberry Pi HQ.

In the announcement of the Raspberry Pi last May, the board was about the size of a USB thumb drive and would cost $25. It looks like the board will be a little larger in the final revision – about the size of a business card – and production of the alpha boards were a bit over cost. That being said, these boards seem a lot more capable than what we’ve seen before. The Raspberry Pi now has 10/100 ethernet, and analog audio and video while keeping the HDMI, USB, and SD card support we saw in the original.

The Raspberry Pi team already has Debian running on these boards, so right now we’re wondering when gumstix boards will come down in price. Of course, this project is intended for use in education, but we can’t wait to see what can be done with this hardware. If you already know what you would do with this, tell us in the comments.

We Don’t Need To Brainstorm Projects; Xkcd Does That For Us

August 23, 2011 by Brian Benchoff 52 Comments

[Randall Munroe], the guy behind our favorite web comic xkcd, gave us yet another great project idea that falls on the heels of securing our valuables and silencing loud car stereos. The xkcd forum has been talking about how to implement this, and we’d like to hear what Hack A Day readers think about this idea.

The project isn’t much different from 3D photography. [Carl Pisaturo] has done a lot of art and experimentation based on this idea that basically amounted to largish binoculars. A poster on the xkcd forum has already built this using mirrors, but we’re wondering how much the parallax can be increased with this method. Two cameras and a smart phone would also allow automatic pan and tilt that corresponds to head movement.

We’re not quite sure if this idea can be applied to astronomy. The angular resolution of the human eye is around one arc minute, every star except for the Sun has an annual parallax less than one arc second. If anyone wants to try this out with a longer baseline (From Earth to Pluto for example), we would suggest simulating this in Stellarium. Seeing the moon as a sphere would be possible with a few hundred miles between cameras, though.

Tell us how you would build this in the comments, and be sure to send in your write-up if you manage to build it. We’ll put it up right away.

Thanks to [Theon144] for sending this in.

EDIT: Because the comments are actually bearing fruit, check out the thread on the Hack A Day forums for this post: link.