Suspicious drones hovering about your property? Burglars or other ne’er-do-well test subjects giving you trouble? Need to catch a dog that keeps meandering through your workshop? [William Osman] suggests you build yourself a pneumatic net gun that can shoot 20-30 feet to catch them all.
The net gun is built largely out of PVC pipe; the air tank — filled via a tire valve — uses adapter fittings to shrink it down to a 1″ sprinkler valve, with an air gun to act as a trigger. The net launcher is made of four lengths of pipe bent with the use of a heat gun — an Occam’s Razor solution compared to his first attempt — and is coupled to the end, while the net loads in using wooden dowels with washers as weights. It won’t trap any large game, but it will certainly net you some fun.
Continue reading “A DIY Net Gun To Catch Whatever You Want”
This is the continuation of a series where I create a PCB in every software suite imaginable. Last week, I took a look at KiCad, made the schematic representation for a component, and made a schematic for the standard reference PCB I’ve been using for these tutorials. Now it’s time to take that schematic, assign footprints to parts, and design a circuit board.
Continue reading “Creating A PCB In Everything: KiCad, Part 2”
This is the continuation of a series of articles demonstrating how to Create A PCB In Everything. In this series, we take a standard reference circuit and PCB layout — a simple ATtiny85 board — and build it with different PCB design tools. Already, we’ve taken a look at the pre-history of PCB design with Protel Autotrax, we learned Fritzing is a joke for PCB design, and we’ve done a deep dive into Eagle. Each of these tutorials serves two purposes. First, it is a very quick introduction to each PCB design tool. Second, this series provides an overall comparison between different PCB design tools.
Now, finally, and after many complaints, it’s time for the tutorial everyone has been waiting for. It’s time for KiCad.
No, like the head of the Bajoran clergy
Although KiCad (pronounced ‘Kai-Cad’ like the head of the Bajoran clergy, not ‘Key-Cad’ like the thing that goes in a lock) is the new hotness when it comes to PCB design. The amazing growth of KiCad installations over the past few years is a long time coming. In development since 1992, KiCad has cemented itself as the premier Open Source PCB design suite, and since 2013 CERN has been making contributions to the project. More recently, the KiCad project has been showing off some amazing new features. These include 3D rendering of boards, interactive routing, push-and-shove, simulation, and dozens of other features that put it on a path to being on par with the top of the line EDA suites. Add in some great community contributions, and you have something really, really amazing. All of this is wrapped up in an Open Source license, free as in speech and beer. If you’re looking for the future of PCB design, Eagle is going to get very good but KiCad is almost there now while being Open Source.
Continue reading “Creating A PCB In Everything: KiCad, Part 1”
It’s generally a bad idea to mix high voltage electricity and water, but interesting things happen if you do. This video from [RWGResearch] shows one of them: water bridging. If you have two water sources (such as two beakers full of very highly distilled water) with a high voltage between them, the voltage can create a gravity defying bridge that flows between them.
The experiment starts with the pouring spouts from two beakers nearly touching each other. Water fills the beakers right up to the spout, but it’s the application of electricity that pulls the bridge between the positive and negative beakers. With care, this technique can create a bridge of up to 2cm (about 0.8 inches). [RWGResearch] shows that he is able to create a bridge of about a centimeter with a 5KV voltage, but which only carries a few milliamps.
What forces are at play here isn’t exactly clear, but one recent paper speculates that it’s down to a combination of the dielectric force caused by the differing charges of parts of water molecules and the surface tension of the water. Whatever it is, it is fascinating and makes for a neat trick.
Want to make your own contribution to the scientific body of knowledge? Prove or disprove the speculation mentioned in the Wikipeadia article: is this possible because of an H3O2 lattice formed by the high voltage? How would you formulate a test for this?
Continue reading “Make Water Bridges With High Voltages”
Protel Autotrax is a PCB design tool first released for DOS in the mid-80s. Consider this a look at the history of PCB design software. I’m not recommending anyone actually use Protel Autotrax — better tools with better support exist. But it’s important to know where we came from to understand the EDA tools available now. I’m rolling up my sleeves (about 30 years worth of rolling) and building our standardized test PCB with the tool. Beyond this, I suggest viewing EEVblog #747, where [Dave] digs into one of his old project, Borland Pascal, and Protel Autotrax.
This is the continuation of a series of articles demonstrating how to Create A PCB In Everything. In this series, we take a standard reference circuit and PCB layout — a simple ATtiny85 board — and build it with different PCB design tools. We’ve already covered Eagle in this series. We learned Fritzing is a joke for PCB design, although it is quite good for making breadboard graphics of circuits. Each of these tutorials serves as a very quick introduction to a specific PCB design tool. Overall, this series provides for a comparison between different PCB design tools. Let’s dig into Protel Autotrax.
A short history of Protel, Altium, and Autotrax
The company we know as Altium today was, for the first fifteen years of its existence, known as Protel. Back in the day, PCB design on a computer required a dedicated workstation, a lot of hardware, light pens, and everything was extraordinarily expensive. Protel was a reaction to this and the first product, Autotrax, was a DOS-based program that brought PCB design to the PC. A freeware version of Autotrax is still available on the Altium website and can be run from inside a DOS virtual machine or DOSBox.
Interestingly, Protel Autotrax is not the only PCB design software named Autotrax. A company called DEX 2020 has also has a PCB design software called AutoTRAX. This is weird, confusing, and I can’t figure out how this doesn’t violate a trademark. If anyone has any insight to what the Protel / Altium legal department was doing a few decades ago, your wisdom is welcome in the comments.
Continue reading “Creating A PCB In Everything: Protel Autotrax”
Halloween has come and gone, but this DIY voice changing Star Wars Stormtrooper helmet tutorial by [Shawn Hymel] is worth a look for a number of reasons. Not only is the whole thing completely self-contained, but the voice changing is done in software thanks to the Teensy’s powerful audio filtering abilities. In addition, the Teensy also takes care of adding the iconic Stormtrooper clicks, pops, and static bursts around the voice-altered speech. Check out the video below to hear it in action.
Besides a microphone and speakers, there’s a Teensy 3.2, a low-cost add-on board for the Teensy that includes a small audio amp, a power supply… and that’s about it. There isn’t a separate WAV board or hacked MP3 player in sight.
Continue reading “Stormtrooper Voice Changer Helmet uses Teensy to Mangle Audio”
What’s the quickest way to turn one game into 2,400? Cram a Raspberry Pi Zero running RetroPie into an NES cartridge and call it Pi Cart.
This elegant little build requires no soldering — provided you have good cable management skills and the right parts. To this end, [Zach] remarks that finding a USB adapter — the other main component — small enough to fit inside the cartridge required tedious trial and error, so he’s helpfully linked one he assures will work. One could skip this step, but the potential for couch co-op is probably worth the effort.
Another sticking point might be Nintendo’s use of security screws; if you have the appropriate bit or screwdriver, awesome, otherwise you might have to improvise. Cutting back some of the plastic to widen the cartridge opening creates enough room to hot glue in the USB hub, a micro USB port for power, and an HDMI port in the resulting gap. If you opted to shorten the cables, fitting it all inside should be simple, but you may have to play a bit of Tetris with the layout to ensure everything fits.
Continue reading “Pi Cart: 2,400 Games In One”