bluetooth

601 Articles

Flight Sim Tracking From Spatial Audio

July 6, 2026 by 9 Comments

Flight sims are wonderful to play around with to get immersed in the position of a pilot. Racing sims can give you a thrill that can only be beaten by the real thing. However, most of this tech is on the more expensive side, so it would be great if you could use some of the hardware already found in your house. Many Sony headphones already have rotation and movement data built in for spatial audio, so why not start there?

[Nicholas Slattery] had this very idea and has produced an open-source application to connect your headphones straight to your sim. There’s a surprising amount of support built into many headsets that use a known protocol called the Android Head Tracker HID protocol. This allowed [Nicholas] to connect a family of Sony headphones straight into OpenTrack, which is often used with flight sims. The best part is you can still use the headphones as normal with a Bluetooth connection.

If you want to give this a try with your own rig, check out [Nicholas]’s GitHub here. While flight and driving sims might be expensive to put together, it’s never too hard to hack together something to lower that barrier! Whether it’s a flight sim force-feedback joystick or driving sim hand-breaks we got you!

Building A Wireless Fingerprint Authorization Device

July 3, 2026 by 13 Comments

Once upon a time, there was a bit of a fad for fingerprint authentication in laptops and desktop computers. It has long since faded, but [superdog] wanted just such a device for Linux and Mac machines. Thus, it was time to build one.

[superdog] designed the device, nicknamed immurok, as a tool for people who use external keyboards, and do lots of terminal work on Mac and Linux machines. Repeat password requests can interrupt one’s flow when hustling at the keys, so immurok was designed to ease this pain.

The device is based on a WCH CH592F microcontroller, which comes with Bluetooth connectivity out of the box. This allows immurok to connect wirelessly to the machine of your choice, advertising itself as a standard Bluetooth HID keyboard device. Fingerprint-wise, scanning is done with an R559S capacitive sensor, which verifies the match locally so there’s no transmitting biometric data anywhere. On the computer side, Linux is setup to use a CLI/TUI app plus PAM integration to handle authorization for system logins and sudo in the terminal. On the Mac platform, it’s used with a menu bar app, with PAM integration for admin prompts. There’s also a separate helper path for using it with the lock screen.

If you’re sick of entering your password all the time and wish unlocking your PC was more like unlocking your phone, this might be the project for you. We’ve seen similar projects before, too. If you’re whipping up fun gear for biometric auth, don’t hesitate to let us know on the tipsline.

A T9 Keyboard For Your Smartphone

June 24, 2026 by 15 Comments

These days, most of us are fortunate enough to use smartphones with decent touchscreen keyboard capabilities. However, once upon a time, if you wanted to type something on a phone, you had to tap it out on the number keys instead. [Jarrett] is bringing that back with a custom T9 keyboard for modern phones. 

The build is designed around the keypad of the Nokia E52, a Symbian smartphone released in 2009—two years after Apple changed the game with the first iPhone. The phone keypad itself is laid over a custom PCB with Alps SKRK tactile switches corresponding to each individual key. Each is wired with a diode and the switches are scanned as a row/column array as is typical for keyboards. Reading the matrix is an ESP32-C6 microcontroller, which counts the keypresses and spits out the right letters over its Bluetooth connection to an attached smartphone or other device. Power is via a small lithium-ion battery, looked after by a TP4200 charger chip.

Overall, the keyboard works as you’d expect, allowing T9-style input to any compatible device that works with Bluetooth keyboards. [Jarrett] does have one regret, with the 0.98 N actuation force switches used leaving he keypad feeling a little mushy. The firmer 1.57 N switches were suspected to give a more satisfying response under thumb, which was a nice upgrade in the second revision build.

We’ve seen other builds in this vein before, too, albeit with bigger keys. If you’re coming up with your own esoteric input methods, don’t hesitate to notify the tipsline.

Custom FM Radio Station Powered By Shell Scripts

June 9, 2026 by 21 Comments

[Trwmato] wanted to spend more time listening to a normal radio to cut back on phone use. But the programming wasn’t quite right so, of course, the solution was to spin up a custom radio station!

The station in question uses a Pi Zero to poll podcasts and news from RSS feeds and automatically mixes them with local content and sends it out via Bluetooth. An FM transmitter allows it to still work on the FM radio, too. Grabbing podcasts isn’t very difficult, thanks to podget. The real logic is in how long to retain things and creating a playlist that both prioritizes fresh content while not repeating things too often. Did we forget to mention the whole thing is a collection of shell scripts?

We could see this as the start of a cool project to have a “radio station” for a school, organization, or company. It is easy to understand and modify.

We often argue that the much-maligned bash script is sometimes the right tool for the job. You can even do things like critical sections in them.

Bluetooth Gramophone Has Surprisingly Contemporary Roots

June 7, 2026 by 17 Comments

So you happen to have a gramaphone– maybe a big old Victrola/HMV, perhaps a Columbia– regardless of brand, it’s a big, beautiful conversation peice for your living room. It might not be the most practical listening device, since isnomuch as there is a vinyl renessance, it’s restricted to vinyl, not the old shellac 78s the these all-mechanical beasts were born for. [JGJMatt] decided to bring his gramophone into the 21st century, turning it into a bluetooth speaker without altering any of its original internals.

What’s really interesting is that this hack was once a commercial product– sort of. Back in the 1920s when everyone was listening to Jazz, the problem of ‘ what do I do with this massive gramophone cabinet when I’m not cutting a rug?’ was equally valid, and a solution was found: the Dulce-Tone Radio Speaker. A very weak speaker sits under the needle, turning the gramaphone mechanism into an amplifier for the radio. The very same concept, [JGJMatt] would work equally well in the 2020s with a bluetooth signal as in the 1920s with an AM one. There’s no demo video for this project, but you can hear how its 1920s inspiration sounded in the video below.

The driver for this device is made using a neodymium magnet and the voice coil from a 3W speaker. A 3D-printed needle-holder captures the gramophone’s needle– a much thicker and sturdier thing than the tiny diamond-tip you’d find on a modern turntable, we should note– and holds the magnet to it. The voice coil gets driven via a MH-M38 bluetooth module, and everything is held in a nice 3D-printed case along with the battery.

The hack is, of course, totally reversible: at any moment, you can remove the needle from this device and drop it on a 78 for some Jazz-era fun, or swap back for 21st century brainrot. If you happen to have some of those old shellac records and a modern turntable, note it takes more than the right RPM to get good sound. Continue reading “Bluetooth Gramophone Has Surprisingly Contemporary Roots” →

Pi Pico Puts Bluetooth Keyboards On The I2C Bus

June 6, 2026 by 2 Comments

If you’ve ever worked with I2C, you know its one of those things that makes working with modern microcontrollers such a pleasure. With a few wires and not many more lines of code, you can communicate with all sorts of hardware such as sensors, displays, and input devices. There are even I2C keyboards out there, although they tend to be a bit pokey — and not in the good way as it pertains to keyboards.

But the bt2i2c project from [Roberto Alsina] promises to improve things. With his firmware flashed to a Pi Pico W, you can establish a connection with any standard Bluetooth keyboard and have the keystrokes sent over the wire via I2C. As far as your project is concerned, the input will appear to be coming from a BlackBerry BBQ20/BBQ10 keyboard using the address 0x1F, which means that there’s already plenty of code out there to work with. While [Roberto] explains its not strictly necessary, connecting a ST7789 display to the Pi Pico over SPI will give you some visual feedback on connection status.

As microcontrollers become increasingly powerful and capable of the sort of thing we would once have done on a “real” computer, a project like this has some fascinating potential. We’ve seen a number of “writerdeck” projects running on chips like the ESP32, and it’s not hard to see the appeal of being able to easily pair your favorite Bluetooth keyboard up to one of them.

If You Want To Hack Me, Come In Through The Speaker

June 4, 2026 by 13 Comments

Some security hacks require someone to have physical access to your computer. In many cases, that’s easy to mitigate. Other attack vectors can put you at risk from anywhere via the network. That’s what firewalls are for. But there is an in-between risk where an attacker just has to be “around” your computer. [Rasmus Moorats] found out that a Creative Sound Blaster sound bar could open up just such an attack.

[Rasmus] was poking around the firmware just to write custom software to control it. The possibility of an attack was just an accidental find.

The soundbar connects to USB, but it also has Bluetooth, which, for some reason, is always on. There’s an app that can communicate with the speaker using BLE, and Creative has a special protocol to control it. The same protocol works on USB or Bluetooth, but with an important difference.

Continue reading “If You Want To Hack Me, Come In Through The Speaker” →