Vintage hi-fi gear can be very attractive, particularly compared to modern stuff. However, when this stuff starts getting into its third or fourth decade after production, things start to wear out. Chief among them—the little incandescent bulbs that light up the dials with such a beautiful glow. [Piffpaffpoltrie] was suffering just this problem on an old Technics amp, and decided to go for a more modern upgrade.
Continue reading “Vintage Audio Amp Gets LED Lighting Upgrade”
This year, we not only challenged Supercon attendees to come up with their own Simple Add-Ons (SAOs) for the badge, but to push the envelope on how the modular bits of flair work. Historically, most SAOs were little more than artistically arranged LEDs, but we wanted to see what folks could do if they embraced the largely unused I2C capability of the spec.
[Squidgeefish] clearly understood the assignment. This first-time attendee arrived in Pasadena with an SAO that was hard to miss…literally. Looking directly at the shockingly bright 128 RGB LED array packed onto the one-inch diameter PCB was an experience that would stay with you for quite some time (ask us how we know). With the “artistically arranged LEDs” aspect of the nominal SAO handled nicely, the extra work was put into the design so that the CPU could control the LED array via simple I2C commands.
Continue reading “Building The Spectacular Fibonacci128 Simple Add-On”
’Tis the season for soldering! At least at my house. My son and I made some fairly LED-laden gifts for the immediate relatives last year, and he’s got the blinky bug. We were brainstorming what we could make this year, and his response was “I don’t care, but it needs to have lots of LEDs”.
It’s also the season for reverse engineering, apparently, because we’re using a string of WS2812-alike “fairy lights”. These are actually really neat, they look good and are relatively cheap. It’s a string of RGB LEDs with drivers, each dipped in epoxy, and run on a common three-enameled-wire bus. Unlike WS2812s, which pass the data on to the next unit in the line and then display them with a latching pulse at the end of a sequence, these LED drivers seem to count how many RGB packets have been sent down the wire, and only respond to their own number.
This means that if you cut up a string of 200 LEDs, it behaves like a string of 200 WS2812s. But if you cut say 10 LEDs off the string, where you cut them matters. If you cut it off the front of the string, you only have to send 10 color packets. If you cut them off the other end, you need to send 290 dummy packets before they even start listening. Bizarre, but ’tis the season for bizarre hacks.
And finally, ’tis the season for first steps into “software architecture”. Which is to say that my son is appreciating functions for the first time in his life. Controlling one LED is easy, but making a light show is about two more abstraction layers on top of that. We’ve been having fun making them dim, twinkle, and chase so far. We only have two more weekends, though, and we don’t have a final light show figured out yet, but after all, ’tis the season for last minute present hacking.
Spoiler alert: almond butter isn’t phosphorescent. But powdered milk is, at least to the limit of detection of this homebrew phosphorescence detector.
Why spend a bunch of time and money on such a thing? The obvious answer is “Why not?”, but more specifically, when [lcamtuf]’s son took a shine (lol) to making phosphorescent compounds, it just seemed natural for dad to tag along in his own way. The basic concept of the detector is to build a light-tight test chamber that can be periodically and briefly flooded with UV light, charging up the putatively phosphorescent compounds within. A high-speed photodiode is then used to detect the afterglow, which can be quantified and displayed.
The analog end of the circuit was the far fussier end of the design, with a high-speed transimpedance amplifier to provide the needed current gain. Another scaling amp and a low-pass filter boosts and cleans up the signal for a 14-bit ADC. [lcamtuf] went to great lengths to make the front end as low-noise as possible, including ferrite beads and short leads to prevent picking up RF interference. The digital side has an AVR microcontroller that talks to the ADC and runs an LCD panel, plus switches the 340 nm LEDs on and off rapidly via a low gate capacitance MOSFET.
Unfortunately, not many things found randomly around the average home are all that phosphorescent. We’re not sure what [lcamtuf] tried other than the aforementioned foodstuffs, but we’d have thought something like table salt would do the trick, at least the iodized stuff. But no matter, the lessons learned along the way were worth the trip.
If you live near Central Park or some other local chess hub, you’re likely never short of opponents for a good game. If you find yourself looking for a computer opponent, or you just prefer playing online, you might like this LED chessboard from [DIY Machines] instead.
At heart, it’s basically a regular chessboard with addressable LEDs of the WS2812B variety under each square. The lights are under the command of an Arduino Nano, which is also tasked with reading button inputs from the board’s side panel. The Nano is interfaced with a Raspberry Pi, which is the true brains of the operation. The Pi handles chess tasks—checking the validity of moves, acting as a computer opponent, and connecting online for games against other humans if so desired. Everything is wrapped up with 3D printed parts, making this an easy project to build for the average DIY maker.
The video tutorial does a great job of covering the design. It’s a relatively simple project at heart, but the presentation is great and it looks awfully fun to play with. We’ve featured some other great builds from [DIY Machines] before, too. Video after the break. Continue reading “Building A Pi-Powered LED Chess Board”
Hewlett-Packard used to make some pretty cool LED displays, many of which appeared in their iconic pocket calculators back in the 1970s and 1980s. [Upir] tracked down some of these classic bubble displays and used them with a microcontroller. We love the results!
The displays featured here, the HPDL-1414, aren’t quite what would have been found in an HP-35, of course. These displays have 16 segments for reasonably legible approximations of most of the ASCII character set. Also, these aren’t just the displays; rather, a pair of the bubble-topped displays, each with four characters, is mounted to a module that provides a serial interface. [Upir] found these modules online, but despite the HP logo on the PCB silkscreen, it’s not really clear who made them. The documentation was a bit thin, to say the least, but with a little translation help from Google, he figured out the serial parameters and the character encoding. The video below shows him putting these modules through their paces.
Unusually for [upir], who has made a name for himself hacking displays to do things they weren’t designed to do, he stuck with the stock character set baked into this module. We think it would be fun to get one of these modules and hack the firmware to provide alternative character sets or even get a few of the naked displays and build a custom interface. Sounds like a fun rainy-day project.
This reminded us of another HP display project we saw a while back. Or, roll your own displays.
We’re big fans of unusual timepieces here at Hackaday, so it didn’t take long before somebody called our attention to the gloriously luminescent watch that [Henner Zeller] was wearing at this year’s Supercon.
He calls it the Glowtape, and it uses a dense array of UV LEDs and a long strip of glow-in-the-dark material to display the time and date, as well as images and long strings of text written out horizontally to create an impromptu banner. It looked phenomenal in person, with the energized areas on the tape glowing brightly during the evening festivities in the alleyway.
Continue reading “Spotted At Supercon: Glowtape Wearable Display”
