DodowDIY Is A Homebrew Sleep Aid

February 23, 2021 by Lewin Day 17 Comments

The Dodow is a consumer device that aims to help users sleep, through biofeedback. The idea is to synchronise one’s breathing with the gentle rhythm of the device’s blue LEDs, which helps slow the heartrate and enables the user to more easily drift off to sleep. Noting that the device is essentially a breathing LED and little more, [Daniel Shiffman] set about building his own from scratch.

An ATTiny85 runs the show; no high-powered microcontrollers are necessary here. It’s hooked up to three 5mm blue LEDs, which are slowly ramped up and down to create a smooth, attractive breathing animation. The LEDs are directed upward so that their glow can be seen on the ceiling, allowing the user to lay on their back when getting ready for sleep. It’s all wrapped up in a 3D printed enclosure that is easily modifiable to suit a variety of battery solutions; [Daniel] chose the DL123A for its convenient voltage and battery life in this case. The design is available on Thingiverse for those looking to spin their own.

It’s a neat example of where DIY can really shine – reproducing a somewhat-expensive gadget that is overpriced for its fundamental simplicity. Now when it comes to waking up again, consider building yourself a nifty smart alarm clock.

Plasma Discharges Show You Where The Radiation Is

February 23, 2021 by Dan Maloney 11 Comments

Depending on the context of the situation, the staccato clicks or chirps of a Geiger counter can be either comforting or alarming. But each pip is only an abstraction, an aural indication of when a particle or ray of ionizing radiation passed through a detector. Knowing where that happened might be important, too, under the right circumstances.

While this plasma radiation detector is designed more as a demonstration, it does a pretty good job at localizing where ionization events are happening. Designed and built by [Jay Bowles], the detector is actually pretty simple. Since [Jay] is the type of fellow with plenty of spare high-voltage power supplies lying around, he took a 6 kV flyback supply from an old build and used it here. The detector consists of a steel disk underneath a network of fine wires. Perched atop a frame of acrylic and powered by a 9 V battery, the circuit puts high-voltage across the plate and the wires. After a substantial amount of tweaking, [Jay] got it adjusted so that passing alpha particles from a sample of americium-241 left an ionization trail between the conductors, leading to a miniature lightning bolt.

In the video below, the detector sounds very similar to a Geiger counter, but with the added benefit of a built-in light show. We like the way it looks and works, although we’d perhaps advise a little more caution to anyone disassembling a smoke detector. Especially if you’re taking apart Soviet-era smoke alarms — you might get more than you bargained for.

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LED Spectrum Visualizer Driven By Raspberry Pi

February 22, 2021 by Lewin Day 19 Comments

Back in the 1980s, spectrum displays on audio equipment were absolutely must have, and the aesthetic came to define the era. This lingered on through the 1990s, and remains a cool look even to this day. [Arduino Guy] decided to put together such a display using a Raspberry Pi and a large LED display.

The LED display in question is of the 64×64 RGB type, available from Aliexpress and other electronics suppliers online. To run the display, an Adafruit RGB Matrix Hat is used with the Raspberry Pi 3B, which makes driving the panel a cinch. The visual effect is run via a Python script, which plays a wave file and produces the spectrum graphics via a Fast Fourier Transform.

While the code isn’t able to act as a general-purpose equalizer display for any content played on the Raspberry Pi, creating such a script could be an entertaining exercise for the reader. Alternatively, the Pi could be hooked up to a microphone to run the display based on ambient room noise. In any case, we’ve seen great projects like this before, such as this laser-based display. Video after the break.

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Custom Inlaid Retro Keycaps: Clay Is The Way

February 19, 2021 by Kristina Panos 10 Comments

They say experience is the best teacher, and experience tells us they are right. When [Thomas Thiel] couldn’t find any resources about re-creating the groovy ‘caps of thocky old keebs like the Space Cadet and the C64 (or find any to buy), it was time for a little keycap experimentation.

These babies are printed in black resin and the inlay is made with white air-dry clay. After printing, they are sprayed with acrylic, and then [Thomas] works a generous amount of clay into the grooves and seals the whole thing with clear spray. [Thomas] soon figured out that the grooves had to be pretty deep for this to work right — at least 1 mm. And he had better luck thick fonts like Arial Black instead of thin fonts.

Of course, as [Thomas] mentions, you’re not restricted to white or even air-dry clay. You could go nuts with colored clay and make a retro-RGB clackable rainbow.

Still not tactile or custom enough for you? These hand-stitched keycaps are technically re-legendable, though it would take a considerable amount of time.

A Smart Way To Wire Smart Switches

February 19, 2021 by Lewin Day 33 Comments

Smart switches are fun, letting you control lights and appliances in your home over the web or even by voice if you’re so inclined. However, they can make day-to-day living more frustrating if they’re not set up properly with regards to your existing light switches. Thankfully, with some simple wiring, it’s possible to make everything play nice.

The method is demonstrated here by [MyHomeThings], in which an ESP8266 is used with a relay to create a basic smart switch. However, it’s wired up with a regular light switch in a typical “traveller” multiway switching scheme – just like when you have two traditional light switches controlling the same light at home. To make this work with the ESP8266, though, the microcontroller needs to be able to know the current state of the light. This is done by using a 240V to 3.3V power supply wired up in parallel with the light. When the light is on, the 3.3V supply is on. This supply feeds into a GPIO pin on the ESP8266, letting it know the light’s current state, and allowing it to set its output relay to the correct position as necessary.

This system lets you use smart lighting with traditional switches with less confused flipping, which is a good thing in our book. If you’re using standalone smart bulbs, however, you could consider flashing them with custom firmware to improve functionality. As always, if you’ve got your own neat smart lighting hacks, be sure to let us know!

Dynamic Macro Keyboard Controls All The Things

February 18, 2021 by Kristina Panos 8 Comments

Keyboard shortcuts are great. Even so, a person can only be expected to remember so many shortcuts and hit them accurately while giving a presentation over Zoom. [Sebastian] needed a good set of of shortcuts for OBS and decided to make a macro keyboard to help out. By the time he was finished, [Sebastian] had macro’d all the things and built a beautiful and smart peripheral that anyone with a pulse would likely love to have gracing their desk.

The design started with OBS, but this slick little keyboard turned into a system-wide assistant. It assigns the eight keys dynamically based on the program that has focus, and even updates the icon to show changes like the microphone status.

This is done with a Python script on the PC that monitors the running programs and updates the macro keeb accordingly using a serial protocol that [Sebastian] wrote. Thanks to the flexibility of this design, [Sebastian] can even use it to control the office light over MQTT and make the CO2 monitor send a color-coded warning to the jog wheel when there’s trouble in the air.

This project is wide open with fabulous documentation, and [Sebastian] is eager to see what improvements and alternative enclosure materials people come up with. Be sure to check out the walk-through/build video after the break.

Inspired to make your own, but want to start smaller? There are plenty to admire around here.

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Custom Firmware For IKEA’s ORSALA Lamp

February 17, 2021 by Lewin Day 29 Comments

These days, home appliances are equally as likely to have soft buttons and rotary encoders as they are to have a simple old clunk/clunk power switch and an analog knob for controls. This is all well and good if the device aligns with your personal philosophy about how such controls should work; otherwise, it’s absolutely maddening. [j-zero] ran into this problem with their ORSALA lamp from IKEA, and set about rectifying the problem with some custom firmware.

The ORSALA lamp uses a rotary encoder for setting both brightness and color temperature, with a button to toggle modes. A long press is required to switch the lamp off. The custom firmware modifies this behaviour, such that the lamp can be switched on and off with a simple button press. Turning the encoder modifies brightness, and turning it to minimum switches the lamp off too. Meanwhile, the less commonly used color temperature setting can be modified by using the button while adjusting the encoder.

The hack was executed by reprogramming the ORSALA’s onboard microcontroller, the STM8S003F3P6, via its SWIM interface. The pads for the interface are easily located on the board, making the hack easy. Other than the inputs, the lamp packs separate TTP932 LED drivers for the warm white and cool white LEDs, making it easy to code a custom firmware to handle all the necessary functions.

It’s a great example of a hacker taking control of their own device and remaking it to suit their needs. Of course, if you want to go for another hacker trope, just stuff a Raspberry Pi in there instead!