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Habit Detection For Home Assistant

2026-02-09 02:00:00

Computers are very good at doing exactly what they’re told. They’re still not very good at coming up with helpful suggestions of their own. They’re very much more about following instructions than using intuition; we still don’t have a digital version of Jeeves to aid our bumbling Wooster selves. [Sherrin] has developed something a little bit intelligent, though, in the form of a habit detector for use with Home Assistant.

In [Sherrin]’s smart home setup, there are lots of things that they wanted to fully automate, but they never got around to implementing proper automations in Home Assistant. Their wife also wanted to automate things without having to get into writing YAML directly. Thus, they implemented a sidecar which watches the actions taken in Home Assistant.

The resulting tool is named TaraHome. When it detects repetitive actions that happen with a certain regularity, it pops up and suggests automating the task. For example, if it detects lights always being dimmed when media is playing, or doors always being locked at night, it will ask if that task should be set to happen automatically and can whip up YAML to suit. The system is hosted on the local Home Assistant instance. It can be paired with an LLM to handle more complicated automations or specific requests, though this does require inviting cloud services into the equation.

We’ve featured lots of great Home Assistant hacks over the years, like this project that bridges 433 MHz gear to the smart home system. If you’ve found your own ways to make your DIY smart home more intelligent, don’t hesitate to notify the tipsline!

Investigating the Science Claims Behind the Donut Solid State Battery

2026-02-08 23:00:22

Earlier this year Donut Lab caused quite the furore when they unveiled what they claimed was the world’s first production-ready solid state battery, featuring some pretty stellar specifications. Since then many experts and enthusiasts in the battery space have raised concerns that this claimed battery may not be real, or even possible at all. After seeing the battery demonstrated at CES’26 and having his own concerns, [Ziroth] decided to do some investigating on what part of the stated claims actually hold up when subjected to known science.

On paper, the Donut Lab battery sounds amazing: full charge in less than 10 minutes, 400 Wh/kg energy density, 100,000 charge cycles, extremely safe and low cost. Basically it ticks every single box on a battery wish list, yet the problem is that this is all based on Donut’s own claims. Even aside from the concerns also raised in the video about the company itself, pinning down what internal chemistry and configuration would enable this feature set proves to be basically impossible.

In this summary of research done on Donut’s claimed battery as well as current battery research, a number of options were considered, including carbon nanotube-based super capacitors. Yet although this features 418 Wh/kg capacity, this pertains only to the basic material, not the entire battery which would hit something closer to 50 Wh/kg.

Other options include surface-redox sodium-ion chemistry with titanium oxide. This too would allow for fast charging and high endurance, but Donut has already come out to state that their battery is not capacitor-based and uses no lithium, so that gets shot down too.

Combined with the ‘cheap’ and ‘scalable’ claims this effectively shoots down any potential battery chemistry and architecture. Barring some amazing breakthrough this thus raises many red flags, especially when you consider Donut Lab’s major promises for investors that should make any reasonable person feel skittish about pouring money into the venture.

Sadly, it seems that this one too will not be the battery breakthrough that we’re all waiting for. Even new chemistries like sodium-ion are struggling to make much of inroads, although lithium-titanate shows real promise. Albeit it not with amazing power density increases that would make it better than plain lithium-ion for portable applications.

Upgrading The E-mu Audity 20 Years After Factory Support Ended

2026-02-08 20:00:49

If you purchased an E-mu Audity 2000 ROMpler back in 1998, you almost certainly got a rig with the 1.00 firmware. It was fine, if a little limited, particularly where upgradability was concerned. E-mu would later offer firmware upgrades over MIDI with the 2.00 firmware, but to get the 2.00 firmware, you needed to ship the box back to E-mu. Or you did… until now.

Realizing that E-mu is long gone and they weren’t going to handle any further firmware upgrades, [Ray Bellis] set about finding another way to help aggrieved operators with gear stuck on v1.00. [Ray] had managed to lay hands on a Audity 2000 service manual as well as the official 2.00 upgrade kit in an estate sale, and set about reverse engineering it to help the community. It turned out that upgrading from 1.00 to 2.00 required the use of a special boot ROM and a flash device containing the upgraded firmware image. Booting from the special ROM required the use of a jumper, and when engaged, the ROM would copy the updated image to the device itself.

[Ray] didn’t want to duplicate the standard upgrade device, as that seemed a little difficult what with parts availability in 2026. Instead, he crafted his own ROM that, with compression, contained the necessary firmware upgrade image and could all be stuffed inside a single 512 KB chip. All you need to do is flash the custom upgrade ROM to an AM29F040B PLCC32 NOR flash chip, pop it in the empty PLCC32 socket on the mainboard, and away you go. This will get you a machine upgraded to the final v2.01 firmware delivered by E-mu before its demise.

It’s a finicky bit of work, but it’s a great way to get new functionality out of an old Audity 2000. We’ve featured similar work before regarding aging Yamaha synths, too. If you’ve got your own backdoor methods for giving older music hardware a new lease on life, don’t hesitate to notify the tipsline.

Upgrading An Old Macbook With an Old Processor

2026-02-08 17:00:15

The Core Duo processor from Intel may not have been the first multi-core processor available to consumers, but it was arguably the one that brought it to the masses. Unfortunately, the first Core Duo chips were limited to 32-bit at a time when the industry was shifting toward 64-bit. The Core 2 Duo eventually filled this gap, and [dosdude1] recently completed an upgrade to a Macbook Pro that he had always wanted to do by replacing the Core Duo processor it had originally with a Core 2 Duo from a dead motherboard.

The upgrade does require a bit more tooling than many of us may have access too, but the process isn’t completely out of reach, and centers around desoldering the donor processor and making sure the new motherboard gets heated appropriately when removing the old chip and installing the new one. These motherboards had an issue of moisture ingress which adds a pre-heating step that had been the cause of [dosdude1]’s failures in previous attempts. But with the new chip cleaned up, prepared with solder balls, and placed on the new motherboard it was ready to solder into its new home.

Upon booting the upgraded machine, the only hiccup seemed to be that the system isn’t correctly identifying the clock speed. A firmware update solved this problem, though, and the machine is ready for use. For those who may be wondering why one would do something like this given the obsolete hardware, we’d note that beyond the satisfaction of doing it for its own sake these older Macbooks are among the few machines that can run free and open firmware, and also that Macbooks that are a decade or older can easily make excellent Linux machines even given their hardware limitations.

555-Based Square-Wave and Triangle-Wave Function Generator Build for Beginners

2026-02-08 14:00:45

The function generator circuit on a breadboard

Over on YouTube [Andrew Neal] has a Function Generator Build for Beginners.

This is the 555 circuit we are building taken from the datasheetAs beginner videos go this one is fairly comprehensive. [Andrew] shows us how to build a square-wave generator on a breadboard using a 555 timer, explaining how its internal flip-flop is controlled by added resistance and capacitance to become a relaxation oscillator. He shows how to couple a potentiometer to vary the frequency.

He then adds an integrator built from a TL082 dual op amp to convert the circuit to a triangle-wave generator, using its second op amp to build a binary inverter. He notes that a binary inverter is usually implemented with a comparator, but he uses the op amp because it was spare and could be put to good use. Again, potentiometers are added for frequency control, in this case a 1 MΩ pot for coarse control and a 10 kΩ pot for fine control. He ends with a challenge to the viewer: how can this circuit be modified to be a sine-wave generator? Sound off in the comments if you have some ideas!

If you’re interested to know more about function generators check out A Function Generator From The Past and Budget Brilliance: DHO800 Function Generator.

A Simple Desktop Pomodoro Timer

2026-02-08 11:00:04

Pomodoro timers are a simple productivity tool. They help you work in dedicated chunks of time, usually 25 minutes in a sitting, before taking a short break and then beginning again. [Clovis Fritzen] built just such a timer of his own, and added a few bonus features to fill out its functionality.

The timer is based around the popular ESP32-S2 microcontroller, which has the benefit of onboard WiFi connectivity. This allows the project to query the Internet for things like time and date updates via NTP, as well as weather conditions, and the value of the Brazilian Real versus the American dollar. The microcontroller is paired with an SHT21 sensor for displaying temperature and humidity in the immediate environment, and an e-paper display for showing timer status and other relevant information. A button on top of the device allows cycling between 15, 30, 45, and 60 minute Pomodoro cycles, and there’s a buzzer to audibly call time. It’s all wrapped up in a cardboard housing that somehow pairs rather nicely with the e-paper display aesthetic.

If Pomodoro is your chosen method of productivity hacking, a project like this could suit you very well. We’ve featured a few similar builds before, too.