[Gautchh] wanted to make something nice for his girlfriend. Being the DIY enthusiast he is, he thought a hand-made gift would resonate with her better than something he could pick up from the store. Enter NeckLight, a glow in the dark PCB necklace. He was first inspired by another project he ran across on Instructables, then decided to put his own little spin on the design. It’s cool how that works. Interestingly enough, it was his first time using Fusion 360, but you probably wouldn’t know that if you took a look at the results.
Aside from soldering, the trickiest part of this project was trying to get the LED intensities just right. [Gautchh] found the best way to do this was experimentally by testing each LED color with a series of resistors. He wanted to ensure he could get the color intensity and the LED current just right. Finally, with a touch of acetone, he was done (though he might want to try some alternatives to acetone next time).
[Gautchh] also thinks that this project would be a really nice way for beginners to learn surface mount (SMD) soldering. We’ve seen a few cool SMD LED projects before. Who could forget those competitive soldering challenges over at DEF CON?
Anyway. Thanks, [Gautchh]. We hope your girlfriend, and your dog, enjoyed their gifts.
In the video game Metro 2033 and its subsequent sequels, players fight their way through a post-apocalyptic version of Russia using improvised weapons and tools cobbled together from the sort of bits and bobs the survivors of a nuclear war might be able to scavenge from the rubble. One of the most useful devices in the game is known as the “Universal Charger”: a hand-operated dynamo that the player must use periodically recharge their electrical devices.
As demonstrated in the video after the break, his charger manages to produce enough energy to light an LED on each squeeze of the trigger. Though if we were packing our gear to go fight mutated beasties in alternate-future Moscow, we might look for something with a bit more kick.
Beyond the 3D printed parts, the charger uses a couple short pieces of 8 mm rod, a NEMA 17 stepper motor, and a one-way bearing that’s usually used for pull starting small gasolene engines.
On Star Trek, all Kirk and friends had to do was snap the button on the always conveniently located intercom panel, start talking, and the intended recipient would immediately respond no matter where they were in the ship. How did it work? Who knows. In spite of, or perhaps even because of, the lightly-explained nature of the technology, the cherry-red wall intercoms still hold a certain charm for fans of the groundbreaking show.
A viewer sent [Fran Blanche] a scaled down replica of the intercom from ThinkGeek, and while it certainly looks fairly close to the original prop, it has a couple of annoying design elements. When triggered by the side-mounted motion sensors, the panel will play either the iconic swoosh of the automatic doors or the “Red Alert” sound effect. It’s a cute idea for a kid’s bedroom maybe, but not exactly ideal for somebody who regularly records YouTube videos.
So the first order of business was to cut the motion sensors out of the circuit and replace them with a push button. [Fran] draws up a quick diagram to explain how these sensors work, and shows that they can easily be bypassed with a momentary switch since they normally bring the line high when triggered. She then converted the indicator light on the right side of the panel into a button to enable the alert sound effect, which is more accurate to how it worked in the show anyway.
The other issue, and perhaps the most egregious to Star Trek fans, is that the “Red Alert” indicator on the top of the panel didn’t actually flash like it did in the show. To design and build this panel and not put a few LEDs behind that piece of frosted plastic seems a bit like producing a Matchbox car and forgetting to make the wheels spin. With a couple of red LEDs and a bit of new wiring, the oversight was quickly rectified.
Even if would never occur to you gift somebody a bootable flash drive, there’s a wealth of information in this blog post about Linux customization which could be useful for all sorts of projects. From creating a bootsplash image to automatically starting up a minimalistic windowing environment so a single graphical application takes center stage.
Whether you’re looking to tweak your desktop machine or build a Raspberry Pi kiosk, the commands and tips that [Stephen] shows off are sure to be interesting for anyone who’s not quite satisfied with how their Linux distribution of choice looks “out of the box”.
But there’s more to this project than a custom wallpaper and some retro fonts. [Stephen] actually took the time to create a facsimile of the “Personal Terminal” computer interface shown in the recent Alien: Isolation game in C using ncurses. The resulting program, aptly named “alien-console”, is released under the BSD license and is flexible enough that you could either use it as a base to build your own cyberpunk UI, or just load it up with custom text files and use it on your cyberdeck as-is.
Finally, to really sell the Alien feel, [Stephen] went through and ripped various audio clips from the film and wove them into the OS so it would make the movie-appropriate boops and beeps. He even included a track of the Nostromo’s ambient engine noise for proper immersion. But perhaps our favorite trick is the use of the sleep command to artificially slow down the terminal and give everything a bit more “weight”. After all, flying a pretend starship should feel like serious business.
Fans of Ghostbusters will remember the PKE meter, a winged handheld device capable of detecting supernatural activity. Precious little technical data on the device remains, leaving us unable to replicate its functionality. However, the flashing, spreading wings serve as a strong visual indicator of danger, and [mosivers] decided this would be perfect for a Geiger counter build.
An SBM20 Geiger tube serves as the detection device, hooked up to an Arduino Nano. An OLED display is used to display the numerical data to the user. The enclosure and folding wings are 3D printed, and fitted with 80s-style yellow LEDs as per the original movie prop.
The device is quite intuitive in its use – if the wings flare out and the lights are flashing faster, you’re detecting an increased level of radiation. In a very real sense, it makes using a Geiger counter much more straightforward for the inexperienced or the hearing impaired. Naturally, there’s also a buzzer generating the foreboding clicks as you’d expect, too.
There was an endless supply of fantastic projects at Supercon this year, but one whose fit and finish really stood out was [Scott]’s lightsaber. If you were walking around and saw someone with a very bright RGB device with a chromed-out handle hanging off their belt it was probably this, though it may have been hard to look at directly. On the outside, the saber looks like a well-polished cosplay prop, and it is! But when Scott quickly broke down the device into component pieces it was apparent that extra care had been put into the assembly of the electronics.
Like any good lightsaber replica the blade is lit, and wow is it bright. The construction is fairly simple, it’s a triplet of WS2812B LED strips back to back on a triangular core, mounted inside a translucent polycarbonate tube with a diffuser. Not especially unusual. But the blade can be popped off the hilt at a moments notice for easy transport and storage, so the strips can’t be soldered in. Connectors would have worked, but who wants flying wires when they’re disconnecting their lightsaber blade. The answer? Pogo pins! Scott runs the power, ground, and data lines out of the strips and into a small board with slip ring-style plated rings. On the hilt, there is a matching array of pogo pins to pass along power and data. The data lines from all the strips are tied together minimizing the number of connections to make, and the outer two power rings have more than one pin for better current-carrying capacity. A handy side effect is that there is nowhere on the blade where there aren’t LEDs; the strips go down to the very end of the blade where it meets the main board inside the hilt.
The hilt is filled with an assembly of 18650’s and a Teensy mounted with a custom shield, all fit inside a printed midframe. The whole build is all about robust design that’s easy to assemble. The main board is book-ended by perpendicular PCBs mounted to the ends, one at the top to connect to the blade and one at the bottom to connect to a speaker. Towards the bottom there is space for an optional Bluetooth radio to allow remote RGB control.
Scott is selling this as a product but also provides detailed instructions and parts lists for each component. Assembly instructions for the blade are here. The hilt is here. And pogo adapters are on OSH Park here. An overview of the firmware with links to GitHub is here. Check out a walkthrough of the handle assembly and blade attachment after the break!
The ticking clock on the bomb is a Hollywood trope that simply refuses to die. Adding to the stress levels of the bomb squad and creating great suspense for the watcher, it’s always interesting to wonder why the average bomb maker is so courteous as to supply this information to law enforcement. Regardless, if you’d like to build a dramatic prop and are mature enough to do so responsibly, [Giorgio] has the guide you need.
The build is a straightforward one, relying on an Arduino to run the show. This is hooked up to a classic 7-segment LED display, upon which the countdown is displayed. For extra flair, an MP3 player is fitted to play the Mission Impossible theme. It all adds to the tension as you wipe the sweat from your brow, trying to decide if you’re cutting the right wire.