Nixie clocks are nothing new. But [CuriousMarc] has one with a unique pedigree: the Apollo Program. While restoring the Apollo’s Central Timing Equipment box, [Marc] decided to throw together a nixie-based clock. The avionics unit in question sent timing pulses and a mission elapsed time signal to the rest of the spacecraft. Oddly enough, while it had an internal oscillator, it was only used during failures. It normally synched to the guidance computer’s onboard clock.
There is a detailed explanation of the unit, along with some of the ancillary equipment and panels. Much of what the output from the unit is driving counters to display timers, although some of the clocks drive other pieces of equipment, like the telemetry commutator, which time stamps each telemetry frame.
With all those e-paper based projects doing the rounds these days, including in our Low Power Challenge, you’d almost forget that monochrome LCDs were the original ultra-low-power display. Without them, we wouldn’t have had watches, calculators and handheld games operating off button cell batteries or tiny solar panels back in the ’80s and ’90s. [Gabor] decided to build a set of gadgets with a 1990s LCD aesthetic, called LCD Solar Creatures. These cute little beasts live on nothing but solar power and provide some amusing animations on a classic seven-segment LCD screen.
The Creatures’ activity depends entirely on the amount of power that’s available to them. If their supercapacitors dip below 3.3 V, their micros enter a deep sleep state and do nothing except briefly flash an LED every now and then as a sign of life. When light hits the solar panel, the supercaps are charged up and the Creatures come to life and display a few basic stats. Once the caps hit 4.1 V, they really start their day and run a few programs, including a Game of Life-style simulation and an animation of Euclidean rhythms. Continue reading “Low Power Challenge: LCD Solar Creatures Live On Sunlight, Sleep At Night”→
The American Birkebeiner is the second largest cross-country skiing race in the world and is quite a big deal within that sport. At 55 kilometers it’s not a short event, either, requiring a significant amount of training to even complete, let alone perform well enough to be competitive. Around a decade ago, friends [Joe] and [Chris] ran afoul of the rules when [Joe] accidentally won the race wearing [Chris]’s assigned entry number, a technicality that resulted in both being banned from the race for two years. Now they’re back, having learned their lesson, and are strictly adhering to those rules this time using these tandem cross-country skis.
The idea for this build was to make sure they could both compete in the race and win because they’d compete in a category no one enters, mostly because it effectively didn’t exist before these two invented it. This required a custom set of skis, but since ski manufacturers don’t typically make skis for two people, they had to get creative. The duo picked up the longest pair of skis they could find at their local ski shop, moving the bindings forward on the skis to make room for the second set of bindings that were added to the back.
This presented a few unique challenges, the first of which is that cross-country skis typically use a special material on the bottom of the skis which grabs the snow to make uphill travel possible, and with the wider distribution of weight this material wasn’t functioning at peak efficiency. The other problem was the stress on the bindings caused by two riders, especially during a crash. This eventually resulted in a broken binding while [Joe] and [Chris] were training. They then upgraded to a more modern pair of skis rated for a single 269-pound rider, had the bindings fitted for two riders, and added a special grip tape over the larger area on the bottom of the ski.
After four months of training and getting in sync, the two were ready for the race. The results are covered in a second video linked below, and while neither of them won the overall race this time, they did finish the event with in-tact skis, first in the new “tandem” class, and completely within the bounds of the strict rules of the race as well. Although winter is winding down in the northern hemisphere, for any of our southern friends looking for some other things to do with an old set of skis for the upcoming winter season, take a look at this sled which adapts some alpine skis to achieve some extremely high speeds.
[Irak Mayer] has been exploring IoT applications for use with remote monitoring of irrigation control systems. As you would expect, the biggest challenges for moving data from the middle of a field to the home or office are with connectivity and power. Obviously, the further away from urbanization you get, the sparser both these aspects become, and the greater the challenge.
[Irak] solves his connectivity problem by assuming there is some WiFi network within range, building a system around the Blues Wireless WiFi note card. Substituting their cellular card would be an option for applications out of WiFi range, but presumably without changing too much on the system and software side of things. Leveraging the Adafruit FeatherWing INA219, which is a bidirectional current sensor with an I2C interface, for both the power generation and system consumption measurements. For control, [Irak] is using an Adafruit ESP32 board, but says little more about the hardware. On the software side, [Irak] is using the Blues Wireless NoteHub for the initial connection, which then routes the collected data onto the Adafruit IoT platform for collation purposes. The final part of the hardware is a LiPo battery which is on standby to soak up any excess power available from the energy harvesting. This is monitored by an LC709203f battery fuel gauge.
The Fisher-Price See ‘n Say was introduced back in 1964, and since then has helped teach countless children the different sounds made by farm animals. But what about our urban youth? If they’re going to navigate a concrete jungle, why not prepare them to identify the sound of a jackhammer or the chime that plays before an announcement goes out over the subway’s PA system?
That’s the idea behind this hacked See ‘n Say [John Park] put together for Adafruit. Now we should note up front that no vintage toys were sacrificed during the production of this gadget — it seems Fisher-Price (predictably) dropped the tiny record player these toys used to use for a cheap electronic board sometime in the 90s. A quick check with everyone’s favorite A-to-Z megacorp shows you can pick up one of these new-school models for around $25 USD.
The modern electronic version of the toy is easy to mod.
Cracking open the electronic version of the See ‘n Say reveals a circular PCB with a series of membrane buttons that are pressed by the mechanics of the spinning pointer. As it so happens, there are handy test points next to each of these buttons, which makes it simple to wire up to a microcontroller.
In this case, it’s Adafruit’s KB2040, which is connected to a MAX98357A amplifier board over I2S. A small boost converter module is used to wring 5 volts out of the toy’s pair of AA batteries. The original speaker is repurposed, though [John] adds a physical power switch to keep the boost converter from flattening the alkaline batteries when not in use.
On the software side, all you’ve got to do is load the MCU with your sounds and write a bit of code that associates them with the button being pressed on the PCB. [John] gets his city sounds from Freesound, a community-maintained database of Creative Commons Licensed sounds, and provides the CircuitPython code necessary to tie everything together.
The last step is the artwork. For this project, [Brian Kesinger] provided some swanky vintage-looking imagery that perfectly fits the See ‘n Say style. The art is available under the NonCommercial-ShareAlike Creative Commons license, so you’re free to use it in your own version. Though naturally, that assumes you’ve decided to use the same sounds as [John] — the beauty of this project is that you could easily load it up with whatever sounds you’d like Hacker Junior to learn. Possibly a well-known Australian YouTuber?
If anyone feels inclined to build a Hackaday-themed See ‘n Say based on this project, we’ve love to see it.
Last year, I found myself compelled to make a scaled-down replica of the iconic test chamber signs from the video game Portal. If you’ve played the game, you’ll remember these signs as the illuminated monoliths that postmarked the start of every test chamber. In hyperstylized video game fashion, they were also extremely thin.
Stay tuned for cake at the end of this article.
True to the original, my replica would need to be both slimmed down and backlit with a uniform, natural white glow. As fate would have it, the crux of this project was finding a way to do just that: to diffuse light coming in from the edges so that it would emit evenly from the front.
What I thought would be quick project ended up being a dive down the rabbit hole that yielded some satisfying results. Today, I’d like to share my findings and introduce you to light guide plates, one of the key building blocks inside of much of today’s backlit screen technology. I’ll dig into the some of the working principles, introduce you to my homebrew approach, and leave you with some inspirational source code to go forth and build your own. Continue reading “A Hacker’s Introduction To DIY Light Guide Plates”→
The Nintendo DSi was surpassed by newer and better handhelds many years ago, but that doesn’t stop people like [Nathan Farlow] from attempting to break into the old abandoned house through a rather unexpected place: the (browser) window.
When the Nintendo DSi was released in 2008, one of its notable features was a built-in version of the Opera 9.50 web browser. [Nathan] reasoned an exploit in this browser would be an ideal entry point, as there’s no OS or kernel to get past — once you get execution, you control the system. To put this plan into action, he put together two great ideas. First he used the WebKit layout tests to get the browser into weird edge cases, and then tracked down an Windows build of Opera 9.50 that he could run on his system under WINE. This allowed him to identify the use-after-free bugs that he was looking for.
Now that he had an address to jump to, he just had to get his code into the right spot. For this he employed what’s known as a NOP sled; basically a long list of commands that do nothing, which if jumped into, will slide into his exploit code. In modern browsers a good way to allocate a chunk of memory and fill it would be a Float32Array, but since this is a 2008 browser, a smattering of RGBA canvases will do.
The actual payload is designed to execute a boot.nds file from the SD card, such as a homebrew launcher. If you want to give it a shot on your own DSi, all you need to do is point the system’s browser to stylehax.net.
