Author: Matt Varian

57 Articles

ESPTimeCastVFD

ESP32 Invades Old TV Box: Forecast More Than Just Channels

October 22, 2025 by 4 Comments

Obsolete hardware is all around us, and some of it has some pretty interesting tech buried within. One such device is an old Belgacom TV Box. Instead of using the ubiquitous LCD screen, it uses a VFD display for its user interface, and [Jean] has taken control of it with the ESPTimeCastVFD project.

Inside this box is a mix of two different 7-segment displays, which he uses to show the time and date, and 12 VFD displays, which are used to show weather data. To get the display working, the box was taken apart, and there were a few different areas [Jean] had to tap into: power for the soon-to-be-embedded ESP32-WROOM-32, as well as tying into the SPI lines to control the VFD. [Jean] also needed a 3.3V to 5V level shifter, and for this he used a 74LS125N dating all the way back to 1978.

The ESPTimeCast project, which we’ve featured here before, handles a lot of the time display and weather forecast shown on the front panel. However, [Jean] did have to add support for the VFD display, as well as adding wind speed to the display—as one of his uses for this is to judge the day’s suitability for flying RC planes. Once powered up, the ESP32 hosts a WiFi access point, allowing you to connect to it and set the configuration of the device, such as location, WiFi credentials, what displays you want to see, and many more. Thank you [Jean] for sending in your hack, saving this device from a landfill by turning it into a personalized display! Be sure to check out some of our other weather displays we’ve featured!

Continue reading “ESP32 Invades Old TV Box: Forecast More Than Just Channels” →

Chicken Squisher 3000

Chicken Squisher 3000: Squish-Proof Security

October 16, 2025 by 21 Comments

Keeping chickens in predator-prone areas demands serious fortifications, but even the most robust coop can become a hassle without automation. That’s where [lcamtuf] steps in with his Chicken Squisher 3000, a clever DIY automatic door mechanism that opens and closes based on ambient light levels.

The chicken coop he previously built did not include a mechanism to automatically close the inner door at night, meaning that arrangements would have to be made should [lcamtuf] want to leave town for a couple of days. Not wanting to go with a commercial option for this door as that would require a good deal of modifications to the original door setup, the Chicken Squisher 3000 adds minimal parts to the existing door to now open and close the door at dawn and dusk.

Using a 12 V DC motor with a gear reduction, he was able to generate more than enough torque to open and close the thick wooden door. Instead of a complex geared rack and pinion setup, [lcamtuf] has the motor mounted to a smooth rod that then applies force across the swing of the door attached with a rod end bearing. Driving the door’s automation is an AVR16DD14 microcontroller which is used to read the NSL-A6009 light sensor. [lcamtuf] uses a DRV8231 motor driver for controlling power going to that 12 V motor with the added benefit of being able to adjust stall torque to dial in a value strong enough to overcome the wooden door’s friction, but weak enough to not endanger any of his birds. There are also buttons on the metal enclosure used to override the light sensor should he want to override it manually.

Thanks, [lcamtuf], for sending in your latest weekend project; we love the resourcefulness of using just a handful of cheap parts to make a robust solution for your coop. If you haven’t seen them yet, be sure to check out some of our other chicken coop door hacks featured before.

RFIDisk

RFIDisk: When Floppy Drives Go Contactless

October 16, 2025 by 14 Comments

Not too long ago, part of using a computer was often finding the correct disk for the application you wanted to run and inserting it into your machine before you could start. With modern storage, this is largely a thing of the past. However, longing for some of that nostalgia, [ItsDanik] has been developing the RFIDisk, a 3D printed floppy drive that can kick off applications when their disk is inserted.

The desktop enclosure is printed to look like a standalone floppy drive, allowing use with either desktops or laptops. There’s the familiar 3.5 inch slot ready for your floppy disk, and there’s also a 1.3 in. OLED display on the front giving you feedback on the status of the RFIDisk — including telling you what’s currently inserted. Inside the enclosure is an Arduino Uno and an MFRC522 RFID reader. As the name would suggest, the way the RFIDisk enclosure reads its media is via NFC, not the traditional magnetic reader. Due to being RFID-based, the disks printed for the RFIDisk are solid without moving parts, but enclose a 25 mm NTAG213 NFC tag.

On the software side, [ItsDanik] has developed the RFIDisk Manager Python application, which is used to tie specific NFC tag IDs to commands to run when that tag is read. The application includes some nice features, such as being able to adjust the commands for both when the disk is first read and when it’s removed from the RFIDisk. You can also change what shows up on the OLED screen when the cartridge is inserted.

Using NFC to simulate physical media is a clever trick we’ve seen before, but if you’re looking for something with a bit more physical engagement, you could always put your USB devices into 3D printed cartridges.

waverider

Waverider: Scanning Spectra One Pixel At A Time

October 13, 2025 by 15 Comments

Hyperspectral cameras aren’t commonplace items; they capture spectral data for each of their pixels. While commercial hyperspectral cameras often start in the tens of thousands of dollars, [anfractuosity] decided to make his own with the Waverider.

To capture spectral data from every pixel location in the camera, [anfractuosity] first needed a way to collect that data — for that, he used an AFBR-S20M2WV, a miniature USB spectrometer he picked up second-hand. This sensor allows for the collection of data from 225 nm all the way up to 1000 nm. Of course, the sensor can only do that for one single input, so to turn it into a camera, [anfractuosity] added a stepper-driven x-y stage controlled by a Raspberry Pi Pico and some TMC2130 stepper drivers.

Continue reading “Waverider: Scanning Spectra One Pixel At A Time” →

BenchVolt PD

BenchVolt PD: USB PD Meets Benchtop Precision

October 10, 2025 by 42 Comments

USB power has become ubiquitous — everything from phones to laptops all use it  — so why not your lab bench? This is what [EEEngineer4Ever] set out to do with the BenchVolt PD USB adjustable bench power supply. This is more than just a simple breakout for standard USB PD voltages, mind you; with adjustable voltages, SCPI support, and much more.

The case is made of laser-cut acrylic, mounted to an aluminum base, not only providing a weighted base but also helping with dissipating heat when pulling the 100 W this is capable of supplying. Inside the clear exterior, not only do you get to peek at all the circuitry but there is also a bright 1.9-inch TFT screen showing the voltage, current, and wattage of the various outputs. There is a knob that can adjust the variable voltage output and navigate through the menu. Control isn’t limited to the knob, mind you; there also is a Python desktop application to make it easy changing the settings and to open up the possibility to integrate its control alongside other automated test equipment.

There are five voltage outputs in this supply: three fixed ones—1.8 V, 2.5 V, and 3.3 V—and two adjustable ones: 0.5-5 V and 2.5-32 V. All five of these outputs are capable of up to 3 A. There are also a variety of waveforms that can be output, blurring the lines between power supply and function generator. While the BenchVolt PD will be open-sourced, [EEEngineer4Ever] will soon be releasing it over on CrowdSupply for those interested in one without building one themselves. We are big fans of USB PD gear, so be sure to check out some other USB PD projects we’ve featured.

Continue reading “BenchVolt PD: USB PD Meets Benchtop Precision” →

splashflag iot swimming notification

Splashflag: Raising The Flag On A Pool Party

October 5, 2025 by 7 Comments

Some things are more fun when there are more folks involved, and enjoying time in the pool is one of those activities. Knowing this, [Bert Wagner] started thinking of ways to best coordinate pool activities with his kids and their neighborhood friends. Out of this came the Splashflag, an IoT device built from the ground up that provides fun pool parties and a great learning experience along the way.

The USB-powered Splashflag is housed in a 3D-printed case, with a simple 2×16 LCD mounted on the front to display the notification. There’s also a small servo mounted to the rear that raises a 3D-printed flag when the notification comes in—drawing your attention to it a bit more than just text alone would. Hidden on the back is also a reset button: a long press factory-resets the device to connect to a different Wi-Fi network, and a quick press clears the notification to return the device to its resting state.

Inside is an ESP32-S3 that drives the servo and display and connects to the Wi-Fi. The ESP32 is set up with a captive portal, easing the device’s connection to a wireless network. The ESP32, once connected, joins an MQTT broker hosted by [Bert Wagner], allowing easy sending of notifications via the web app he made to quickly and easily send out invitations.

Thanks, [Bert Wagner], for sharing the process of building this fun, unique IoT device—be sure to read all the details on his website or check out the code and design files available over on his GitHub. Check out some of our other IoT projects if this project has you interested in making your own.

Continue reading “Splashflag: Raising The Flag On A Pool Party” →

DIY astrophotography camera

Cold Sensor, Hot Results: Upgrading A DSLR For Astrophotography

October 3, 2025 by 16 Comments

When taking pictures of the night sky, any noise picked up by the sensor can obscure the desired result. One major cause of noise in CMOS sensors is heat—even small amounts can degrade the final image. To combat this, [Francisco C] of Deep SkyLab retrofitted an old Canon T1i DSLR with an external cooler to reduce thermal noise, which introduces random pixel variations that can hide faint stars.

While dedicated astrophotography cameras exist—and [Francisco C] even owns one—he wanted to see if he could improve an old DSLR by actively cooling its image sensor. He began with minor surgery, removing the rear panel and screen to expose the back of the sensor. Using a sub-$20 Peltier cooler (also called a TEC, or Thermoelectric Cooler), he placed its cold side against the sensor, creating a path to draw heat away.

Reassembling the camera required some compromises, such as leaving off the LCD screen due to space constraints. To prevent light leaks, [Francisco C] covered the exposed PCBs and viewfinder with tape. He then tested the setup, taking photos with the TEC disabled and enabled. Without cooling, the sensor started at 67°F but quickly rose to 88°F in sequential shots. With the TEC enabled, the sensor remained steady at 67°F across all shots, yielding a 2.8x improvement in the signal-to-noise ratio. Thanks to [Francisco C] for sharing this project! Check out his project page for more details, and explore our other astrophotography hacks for inspiration.

 

 

Continue reading “Cold Sensor, Hot Results: Upgrading A DSLR For Astrophotography” →