It’s time for everyone’s favorite comment thread game: Real or Fake? This week’s edition comes in from a tip that [Fabian] sent us about the music video Bright Siren by the band Androp. The video starts by showing bundles of cables being sorted and connected to breadboards. We get a brief shot of a large LED matrix (presumably being used for testing purposes) then footage of a lot of DSLR cameras with external flashes. These are mounted on racks to produce the marquee seen in the image above. The band performs in front of it for the rest of the video.

We’ve embedded the original video, as well as a ‘making of’ video after the break. There’s also a website you can checkout that lets you write your own message on the marquee. That bit could be easily done in flash so there’s no que, you’ll notice there’s no live feed. While we think the theory is real, we’re a bit skeptical about whether this performance is real or video editing magic. In the behind the scenes clip you can see breadboards attached to each camera flash with rubber bands so we’d guess that at least some of the hardware was setup. But we’re wondering if the animated effects were done in editing like that tea light animation. Let us know what you think by leaving a comment.

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Instructables user [Rohit] had an out-of-warranty microwave with a broken membrane keypad. Much like our friend [Alexandre] from Brazil, he found the cost of replacement parts beyond reasonable, so he had to find a way to repair it instead.

He disassembled the front cover of his microwave to get at the main controller board. Once it was detached, he removed the keypad’s cover to get a closer look at the matrix underneath. While taking notes on how the matrix was wired, he found that some keypad traces connected to other traces rather than buttons. He says that they are likely used by the microwave to detect that the keypad is present, so he made sure to short those traces out on the controller board when he wired everything back together.

He replaced the aging keypad with microswitches, but rather than mount them on the front panel of the microwave, he drilled holes for each switch so that he could mount them inside the face plate. Once everything was wired and glued in place, he re-mounted the keypad’s cover. Now the microwave looks stock but has firm, reliable, user-serviceable buttons that are sure to last quite a while.

[Alexandre Souza] needed a microwave pretty badly, but he didn’t have a lot of cash on hand. He located one for a great price, but once he got home he found that things weren’t working quite like they should be (Google translation).

After some investigation, he narrowed the problem down to a bad keypad membrane. Unfortunately for him, this model of microwave was never sold in Brazil (who knows how it got there) and the only membrane he could track down had to be shipped in from the US at a cost of $80.

Rather than pay such a high price for a simple membrane, he opted to fix the microwave himself. He dismantled the control panel and thoroughly traced the keypad matrix to get an understanding of which pins toggled which functions. With a piece of protoboard and almost two dozen push buttons in hand, he built his own keypad and wired it directly into the microwave’s control board.

With labels written in marker it might not be the nicest looking thing you have ever seen, but it works a treat and is a great money-saving hack.

[Mathieu] was on holiday in China and picked up some fun toys while perusing the numerous electronics markets there. The most interesting things he discovered were a pair of RGB LED matrices. They came in two different flavors, one made for indoor and one for outdoor displays, sporting a 64×32 and 32×16 resolution, respectively.

If you’ve read his blog before you know he is a big fan of LED matrices, so it’s only natural that bought a whole bunch of them and started experimenting once he got home. Using the same Amtel FPSLIC LED matrix control board he showed off in this previous hack, he was able to get the LED matrices up and running in no time. He adapted his webcam project to utilize the new panels, and he added a whole new feature as well. Via MatLab, he can now display any sort of animated gif on the panels, as you can see in the video below. The panels look great, and if we had a few of these around, there’s no doubt we would probably play this video on infinite repeat.

He says that the despite their somewhat questionable origins, the panels are of top notch quality, and he is willing to organize some sort of group buy if others are interested.

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[Stephen] wrote in to show us this fun LED wall he constructed in his house. He says he was inspired by this project, but found the cost of the BlinkM units from sparkfun to be out of his price range. He really liked how they worked though, so he downloaded the schematic and firmware and built his own. He was able to fabricate 130 of his own for roughly 250 euros as opposed to the 1,452 euro price tag his sparkfun shopping cart had. That’s not a bad deal at all if you’re willing to invest the time in making your own PCBs and assembling the units. You can follow along on his site to see the entire construction process, as well as some pictures of his glass wall in action. The videos, however, aren’t loading for us. Great job [Stephen]!

Instructables user [llopez-garcia] was looking for something that would make him stand out at music events or clubs, and decided that an LED matrix built into a set of sunglasses would do the trick.

He grabbed some LEDs and the biggest pair of sunglasses he could find at WalMart, then he got down to business. He had no experience in programming micro controllers, so he chose a PICAXE 20X2 to run his glasses, figuring that it would be easier to program in BASIC for his first project than C.

He drilled holes in the lenses and wired up two 5×5 LED grids, connecting them to the PICAXE as a single 10×5 array. That setup was chosen because the 20X2 limited him to 15 usable pins and he wanted to avoid using a shift register or LED driver to keep the part count down. The rest of the build is relatively straightforward with resistors in all the right places, and a pair of AAA batteries to power it – one strapped to either temple.

We think these are pretty cool, though we’re not sure if he can see anything while wearing them. Then again, who cares? You don’t need to be able to see with glasses this awesome.

If he had to do it all over again, [llopez-garcia] says he would beef up the LED structure a bit, as well as choose a different micro controller that can be programmed in C since he felt the PICAXE was a bit limited by BASIC.

Stick around to see a quick demo video of the glasses in action.

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[Rajendra Bhatt] wrote in to share a tutorial he put together demonstrating the basics of using LED dot matrix displays. While this subject might be old hat to many out there, his helpful walkthroughs are geared more towards beginners who are exploring various electronics concepts for the first time.

He explains the theory behind LED displays using a PIC-driven 5×7 matrix as an example. He discusses persistence of vision and how tricking the human eye can save you quite a bit of time and a whole lot of pins. Multiplexing is broken down into its most basic steps, which [Rajendra] illustrates by showing how a letter would be drawn on the LED display one column at a time. The use of a ULN2803A Darlington Array is also discussed, and he details why it is used when pulling the five columns of LEDs to ground.

The only portion of the tutorial we thought could be expanded upon was the programming section. While he does show how each letter of the alphabet can be displayed via a series of five hex values, he does not cover the “why” part of the process. Obviously while anyone familiar with binary and hex can figure it out in pretty short order, we think that it would be a great place to pause and expand the readers’ knowledge even more.

Overall it’s a useful tutorial, and most beginners would likely find it quite helpful.

[Mathieu] has bee working to refine the code running on an LED matrix, and added some neat display tricks along the way. He wanted to make the display directly addressable from a computer. The 96×64 bi-color LED display is powered by an Atmel FPSLIC and already used double-buffering. Enabling a PC to write directly to one of the buffers was not too hard, requiring just a bit of optimization to get the timing right. From the look of the video after the break, he nailed it.

The video feed is generated from a webcam stream using Matlab to process each image. Just 50 lines of code captures a frame, sizes it appropriately, converts the result to black and white for edge detection, then finishes the job by compressing image data for transmission to the embedded processor. We’d like to say it’s easier that it sounds but we’re pretty impressed with this work. The display manages about 42 Hz with the current setup.

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