If you flew or drove anything remote controlled until the last few years, chances are very good that you’d be using some faceless corporation’s equipment and radio protocols. But recently, open-source options have taken over the market, at least among the enthusiast core who are into squeezing every last bit of performance out of their gear. So why not take it one step further and roll your own complete system?

Apparently, that’s what [Malcolm Messiter] was thinking when, during the COVID lockdowns, he started his own RC project that he’s calling LockDownRadioControl. The result covers the entire stack, from the protocol to the transmitter and receiver hardware, even to the software that runs it all. The 3D-printed remote sports a Teensy 4.1 and off-the-shelf radio modules on the inside, and premium FrSky hardware on the outside. He’s even got an extensive folder of sound effects that the controller can play to alert you. It’s very complete. Heck, the transmitter even has a game of Pong implemented so that you can keep yourself amused when it’s too rainy to go flying.

Of course, as we alluded to in the beginning, there is a healthy commercial infrastructure and community around other open-source RC projects, namely ExpressLRS and OpenTX, and you can buy gear that runs those software straight out of the box, but it never hurts to have alternatives. And nothing is easier to customize and start hacking on than something you built yourself, so maybe [Malcolm]’s full-stack RC solution is right for you? Either way, it’s certainly impressive for a lockdown project, and evidence of time well spent.

Thanks [Malcolm] for sending that one in!

Bears! Are they scared of massive arcs that rip through the air, making a lot of noise in the process? [Jay] from the Plasma Channel sure hopes so, because that’s how his bear deterrent works!

[Jay] calls it the Bear Blaster 5000. Right from the drop, this thing looks like some crazy weapon out of Halo. That’s because it throws huge arcs at 280,000 volts. The basic concept behind it is simple enough—a battery drives a circuit which generates (kinda) low voltage AC. This is fed to the two voltage multipliers which are set up with opposite polarity to create the greatest possible potential difference between the two electrodes they feed. The meaty combination is able to arc across electrodes spaced over four inches apart. It’s all wrapped up in a super-cool 3D printed housing that really shows off the voltage multiplier banks.

Given its resemblance to a stun gun, you might think the idea is to jab an attacking bear with it. But the reality is, if the bear is close enough that you could press this device against it, you’re already lunch. [Jay] explains that it’s more about scaring the animal off with the noise and light it produces. We’d certainly take a few steps back if we heard this thing fire off in the woods.

[Jay] does a great job of explaining how the whole setup works, as well as showing off its raw ability to spark. We’ve seen some great builds from [Jay] before, too, like this beefy custom flyback transformer.