Make Your Ceiling Disappear With ADS-B And Short-Throw Projector

If you’re into airplanes, you’ve probably had the experience of hearing an unusual aircraft and rushing outside to try and catch a glimpse of it, all while fumbling with a smartphone to open a flight-tracking app. If your home was equipped with [cpaczek]’s Skylight project, which combines ADS-B data with a short throw projector, that little dance would have been totally unnecessary.

ADS-B or the “Automatic Dependent Surveillance-Broadcast”, is the standard by which aircraft broadcast their position and other flight information from onboard transponders. In most of the world, every commercial aircraft has an ADS-B transmitter, and they’re slowly creeping into general aviation as well. The signals aren’t hard to pick up with software-defined radio — like perhaps this RP2040 based unit we featured — or the RTL-SDR v4 this project calls for.

Using data from ADS-B, the Skylight software runs on Raspberry Pi 5 and renders icons of the aircraft exactly where they would appear above you, if that pesky ceiling wasn’t in the way. You get the flight’s code, destination and flightplan with a nice icon representing what type of airplane it is. Thanks to specifying a Pi 5, the projection is a smooth 60 FPS at 1080p. Airplanes aren’t the only things plotted, though — this is also a planetarium, giving you a full view of the stars and any satellites passing overhead. That’s obviously via an API, not SDR, and if you like you can configure it to track aircraft that way to — allowing you to set your Skylight for anywhere in the world, if you aren’t near an interesting airport.

ADS-B isn’t just for pilots and plane nerds — if you’re flying drones, you probably should keep an eye on it, too. In that case, though, you probably won’t be looking at your ceiling.

Thanks to [Thinkerer] for the tip!

Fixing A Nintendo Game Boy Clone That Runs Too Fast

There’s no shortage of cloned Nintendo hardware out there, and most of it is pretty poor. A few are actually pretty interesting though, such as the GB Boy by Gangfeng, which takes real cartridges and thus in many ways should provide the original Game Boy Pocket experience with modern hardware. But as you might imagine, even the best of the clones comes with various technical issues at no additional charge — with this particular unit having a habit of running the game too fast. It’s an issue that [Sharopolis] addresses in a recent video with a partial fix.

As can be seen in the demonstration, it runs games just too fast to make it very usable or fun, hence why it sat in a drawer for a few years after purchasing off AliExpress. This raises the question of what’s wrong with these units, as others report similar issues with this and other ‘GB Boy’ variants.

Fortunately the unit is easy to open, revealing the PCB with a couple of chips on it, one marked KF2001 being the brains of the operation alongside two memory chips. The crystal resonator marked X1 for the main IC is rated for 5 MHz, whereas a quick look inside the Game Boy Pocket shows that its crystal resonator runs at 4.1943 MHz, which is a bit of a difference.

Because of how buying components and pricing works, [Sharopolis] ended up with a reel of 100 of replacement resonators with the right parameters for a drop-in replacement. After swapping the resonator, the GB Boy now does indeed run games at the right speed, but a new issue has now cropped up in the form of flicker on the display.

In the comments it’s suggested that replacing the cheap capacitors on the GB Boy’s board can help here, but it highlights just how these clone systems keep managing to snatch defeat from the jaws of victory by pairing what looks to be a pretty good IC with either the wrong or sub-par components.

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