Dark lab setup with scientific looking drink dispenser

Scared For A Drink?

October 31, 2025 by Heidi Ulrich 1 Comment

Halloween is about tricks and treats, but who wouldn’t fancy a bit to drink with that? [John Sutley] decided to complete his Halloween party with a drink dispenser looking as though it was dumped by a backstreet laboratory. It’s not only an impressive looking separating funnel, it even runs on an Arduino. The setup combines lab glassware, servo motors, and an industrial control panel straight from a process plant.

The power management appeared the most challenging part. The three servos drew more current than one Arduino could handle. [John] overcame voltage sag, brownouts, and ghostly resets. A healthy 1000 µF capacitor across the 5-volt rail fixed it. With a bit of PWM control and some C++, [John] managed to finish up his interactive bar system where guests could seal their own doom by pressing simple buttons.

This combines the thrill of Halloween with ‘the ghost in the machine’. Going past the question whether you should ever drink from a test tube – what color would you pick? Lingonberry juice or aqua regia, who could tell? From this video, we wouldn’t trust the bartender on it – but build it yourself and see what it brings you!

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Testing Cheap DC Breakers And How To Not Start Fires

October 28, 2025 by Maya Posch 11 Comments

One characteristic of adding PV solar to homes is a massive increase in high-voltage and high-current DC installations. With this comes a need for suitable breakers, but without the requisite knowledge it can be easy to set up a fire hazard. There is also the issue of online shopping platforms making it easy to get fuses and breakers that may not be quite as capable as they claim, never mind being rated for DC use.

Recently [Will Prowse] had a poke at a range of common purportedly DC-rated breakers from everyone’s favorite US-based seller of tat, to see whether they should be bought or avoided at all cost. Perhaps unsurprisingly the cheap breakers are about as dodgy as you’d imagine. With a hundred plus amps flowing through them they get surprisingly crispy, even if they generally did their job. Minus the few that arrived in a broken condition, of course.

Ultimately [Will] found that the molded case circuit break (MCCB) by one ‘DIHOOL’ performed the best. Compared to the competition, it is much larger and has sizeable terminals that avoid the quaint heat-soaking issues seen with the cheap-and-cheerful rest. At a mere $34 for the 125A-rated version, it’s still a fraction of the cost of a comparable Eaton MCCB, but should upset your insurance company significantly less than the alternatives.

Don’t forget to add in fuses, with [Will] testing a range of cheapo 12V DC fuses, to see which one will prevent fires, and which one cause them. Unsurprisingly, some of them like the Bojack-branded ones ran very hot, making them more of a liability than an asset.

As for what makes DC breakers so different from AC one is that the extinguishing point of a DC arc is much steeper, which means that an AC breaker is likely to fail to extinguish the arc when used for DC applications. This is why a properly rated and ideally certified breaker is essential, and also not really the point where you want to start saving money.

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HRV Gets Home Automation Upgrades

October 26, 2025 by Bryan Cockfield 5 Comments

In our modern semi-dystopia, it seems like most companies add automation features to their products to lock them down and get consumers to buy even more proprietary, locked-down components. The few things that are still user-upgradable are getting fewer and farther between, but there are still a few things that can be modified and improved to our own liking like this control panel for a heat recovery ventilator (HRV).

HRVs are systems that exchange fresh, outside air with stale, inside air while passing them both through a heat exchanger to keep from wasting energy. Many systems run continuously but they aren’t always needed, so some automation is beneficial. This upgrade from [vincentmakes] improves the default display for a Zehnder Comfoair Q350 HRV with a color display as well as adding it in to a home automation system, letting a user control fan speeds remotely as well as alerting the user when it’s time for filter replacements and providing up-to-date information from all the sensors in the HRV.

The project builds on a previous project which adapted an ESP32 to interact with the CAN bus used on these devices. With these upgrades the user can forgo the $300 proprietary upgrade that would be needed to get the same functionality otherwise. It’s also fully open-source so all that’s needed is to flash the firmware, replace the display, and enjoy the fresh air. There’s other modern HVAC equipment that can benefit from new controllers and a bit of automation as well.

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Kitchen Bench Splash Guard Powered By Arduino

October 22, 2025 by Lewin Day 40 Comments

If you’re blessed with high water pressure at home, you probably love how it helps blast grime from your dishes and provides a pleasant washing experience. However, it can also cause a wonderful mess when that water splashes all over your countertops. [vgmllr] has whipped up a simple solution to this problem by installing an automatic splash guard.

The concept is simple enough—install a pair of flat guards that raise up when the sink is running, in order to stop water getting everywhere. To achieve this, [vgmllr] grabbed an Arduino, and hooked it up to a piezo element, which acts as a water sensor.

The piezo is attached to the bottom of the sink, and effectively acts as a microphone, hooked up to one of the Arduino’s analog-to-digital pins. When water flow is detected, the Arduino commands two servos to raise a pair of 3D printed arms that run up and down the outside of the sink. Each arm is fitted with magnets, which mate with another pair of magnets on the splash shields inside the sink. When the arms go up, the splash shields go up, and when the arms go down, the splash shields go down.

It’s an ingenious design, mostly because the installation is so clean and seamless. By using magnets to move the splash shields, [vgmllr] eliminated any need to drill through the sink, or deal with any pesky seals or potential water leaks. Plus, if the splash shields are getting in the way of something, they can easily be popped off without having to disassemble the entire mechanism.

It’s a tidy little build, both practical and well-engineered. It’s not as advanced as other kitchen automations we’ve seen before, but it’s elegant in its simple utility.

Billy Bass Gets New Job As A Voice Assistant

October 9, 2025 by Bryan Cockfield 8 Comments

For those who were alive and conscious before the modern Internet, there were in fact things that went “viral” and became cultural phenomenon for one reason or another. Although they didn’t spread as quickly or become forgotten as fast, things like Beanie Babies or greeting a friend with an exaggerated “Whassup?” could all be considered viral hits of the pre-Internet era.

Another offline hit from the late 90s was the Billy Bass, an absurdist bit of physical comedy in the form of a talking, taxidermied fish. At the time it could only come to life and say a few canned lines, but with the help of modern hardware it can take on a whole new life.

This project comes to us from [Cian] who gutted the fish’s hardware to turn it into a smart voice assistant with some modern components, starting with an ESP32 S3. This chip has enough power to detect custom “wake words” to turn on the fish assistant as well as pass the conversation logic to and from a more powerful computer, handle the audio input and output, and control the fish’s head and tail motors. These motors, as well as the speaker, are the only original components remaining. The new hardware, including an amplifier for the speaker, are mounted on a custom 3D printed backplate.

After some testing and troubleshooting, the augmented Billy was ready to listen for commands and converse with the user in much the same way as an Alexa or other home assistant would. [Cian] built this to work with Home Assistant though, so it’s much more open and easier to recreate for anyone who still has one of these pieces of 90s kitch in a box somewhere.

Perhaps unsurprisingly, these talking fish have been the basis of plenty of hacks over the years since their original release like this one from a few years ago that improves its singing ability or this one from 2005 that brings Linux to one.

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Smart Bulbs Are Turning Into Motion Sensors

October 7, 2025 by Lewin Day 33 Comments

If you’ve got an existing smart home rig, motion sensors can be a useful addition to your setup. You can use them for all kinds of things, from turning on lights when you enter a room, to shutting off HVAC systems when an area is unoccupied. Typically, you’d add dedicated motion sensors to your smart home to achieve this. But what if your existing smart light bulbs could act as the motion sensors instead?

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Logitech POP Buttons Are About To Go Pop

October 6, 2025 by Maya Posch 70 Comments

For those who missed out on the past few years of ‘smart home’ gadgets, the Logitech POP buttons were introduced in 2018 as a way to control smart home devices using these buttons and a central hub. After a few years of Logitech gradually turning off features on this $100+ system, it seems that Logitech will turn off the lights in two weeks from now. Remaining POP Button users are getting emails from Logitech in which they are informed of the shutdown on October 15 of 2025, along with a 15% off coupon code for the Logitech store.

Along with this coupon code only being usable for US-based customers, this move appears to disable the hub and with it any interactions with smart home systems like Apple HomeKit, Sonos, IFTTT and Philips Hue. If Logitech’s claim in the email that the buttons and connected hub will ‘lose all functionality’, then it’d shatter the hopes for those who had hoped to keep using these buttons in a local fashion.

Suffice it to say that this is a sudden and rather customer-hostile move by Logitech. Whether the hub can be made to work in a local fashion remains to be seen. At first glance there don’t seem to be any options for this, and it’s rather frustrating that Logitech doesn’t seem to be interested in the goodwill that it would generate to enable this option.