[Rick] had a problem. His garage refrigerator was tasked with a critical duty—keeping refreshing beverages at low temperature. Unfortunately, it had failed—the condenser was forever running, or not running at all. The beverages were either frozen, or lukewarm, regardless of the thermostat setting. There was nothing for it—the controller had to be rebuilt from scratch.

Thankfully, [Rick]’s junk drawer was obliging. He was able to find an Arduino Uno R4, complete with WiFi connectivity courtesy of the ESP32 microcontroller onboard. This was paired with a DHT11 sensor, which provided temperature and humidity measurements. [Rick] began testing the hardware by spitting out temperature readings on the Uno’s LED matrix.

Once that was working, the microcontroller had to be given control over the fridge itself. This was achieved by programming it to activate a Kasa brand smart plug, which could switch mains power to the fridge as needed. The Uno simply emulated the action of the Kasa phone app to switch the smart plug on and off to control the fridge’s temperature, with the fridge essentially running flat out whenever it was switched on. The Uno also logs temperature to a server so [Rick] can make sure temperatures remain in the proper range.

We’ve seen some great beverage-cooling hacks over the years. If you’ve mastered your own hacky methods of keeping the colas chilled, don’t hesitate to let us know on the tipsline.

Connected devices are ubiquitous in our era of wireless chips heavily relying on streaming data to someone else’s servers. This sentence might already start to sound dodgy, and it doesn’t get better when you think about today’s smart glasses, like the ones built by Meta (aka Facebook).

[sh4d0wm45k] doesn’t shy away from fighting fire with fire, and shows you how to build a wireless device detecting Meta’s smart glasses – or any other company’s Bluetooth devices, really, as long as you can match them by the beginning of the Bluetooth MAC address.

[sh4d0wm45k]’s device is a mini light-up sign saying “GLASSHOLE”, that turns bright white as soon as a pair of Meta glasses is detected in the vicinity. Under the hood, a commonly found ESP32 devboard suffices for the task, coupled to two lines of white LEDs on a custom PCB. The code is super simple, sifting through packets flying through the air, and lets you easily contribute with your own OUIs (Organizationally Unique Identifier, first three bytes of a MAC address). It wouldn’t be hard to add such a feature to any device of your own with Arduino code under its hood, or to rewrite it to fit a platform of your choice.

We’ve been talking about smart glasses ever since Google Glass, but recently, with Meta’s offerings, the smart glasses debate has reignited. Due to inherent anti-social aspects of the technology, we can see what’d motivate one to build such a hack. Perhaps, the next thing we’ll see is some sort of spoofed packets shutting off the glasses, making them temporarily inoperable in your presence in a similar way we’ve seen with spamming proximity pairing packets onto iPhones.

We absolutely adore inspired labor-of-love tales such as this one. [Alastair] wanted to build a synth for his daughter’s third birthday in spite of having no prior hardware knowledge. It became the perfect excuse to learn about CAD, microcontrollers, PCB design, and of course, 3D printing.

So, why a synth for a toddler? Aside from plain old ‘why not?’, the story goes that she received a Montessori busy-type board which she seemed to enjoy, and it reminded [Alastair] of the control surface of a synth. He wondered how hard it could be to build something similar that made sound and didn’t require constant button presses.

[Alastair] began his journey by dusting off a 15-year-old Arduino Inventors Kit. The initial goal was to get potentiometer readings and map them to 12 discrete values, and then emit MIDI messages. This was easy enough, and it was time to move to a synth module and an Elegoo Nano.

The full adventure is definitely worth the read. Be sure to check out the pink version in action after the break. You really don’t wanna miss the lil’ panda bear. Trust us.

Thanks for the tip, [dole]!