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July 15, 2024July 16, 2024

Linux 6.10 Release – Notable changes, Arm, RISC-V, and MIPS architectures

Linux Torvalds has announced the release of Linux 6.10 on LKML: So the final week was perhaps not quote as quiet as the preceding ones, which I don’t love – but it also wasn’t noisy enough to warrant an extra rc. And much of the noise this last week was bcachefs again (with netfs a close second), so it was all pretty compartmentalized. In fact, about a third of the patch for the last week was filesystem-related (there were also some btrfs latency fixes and other noise), which is unusual, but none of it looks particularly scary. Another third was drivers, and the rest is “random”. Anyway, this obviously means that the merge window for 6.11 opens up tomorrow. Let’s see how that goes, with much of Europe probably making ready for summer vacation. And the shortlog below is – as always – just the last week, not some kind […]

May 13, 2024

Linux 6.9 release – Main changes, Arm, RISC-V, and MIPS architectures

Linus Torvalds has just announced the release of Linux 6.9 on LKML: So Thorsten is still reporting a few regression fixes that haven’t made it to me yet, but none of them look big or worrisome enough to delay the release for another week. We’ll have to backport them when they get resolved and hit upstream. So 6.9 is now out, and last week has looked quite stable (and the whole release has felt pretty normal). Below is the shortlog for the last week, with the changes mostly being dominated by some driver updates (gpu and networking being the big ones, but “big” is still pretty small, and there’s various other driver noise in there too). Outside of drivers, it’s some filesystem fixes (bcachefs still stands out, but ksmbd shows up too), some late selftest fixes, and some core networking fixes. And I now have a more powerful arm64 machine […]

$35 SONOFF POW ring smart power meter (POWCT) safely supports up to 100A

SONOFF POW Ring smart power meter is the first CT clamp-based WiFi power meter from ITEAD. It is designed for installation in an electric cabinet to measure whole-house power consumption with up to 100A current. The power meter relies on an ESP32 microcontroller for control and wireless connectivity with a range of up to 130 meters thanks to an external high-gain antenna. It is supported by the usual eWelink mobile app that also enables integration with Google Home, Amazon Alexa, and IFTTT services, and ITEAD also mentions integration with the Home Assistant open-source framework. SONOFF POW Ring (POWCT) specifications: MCU – ESP32 WiFi and Bluetooth microcontroller Connectivity – 2.4 GHz WiFi 4 (802.11b/g/n) with SMA antenna connector for an external antenna to be placed outside of the electrical cabinet Current transformer (CT) interface type – RJ9 Current transformer detection range – 0 to 100A Measurement category – CAT II 0-100A […]

October 11, 2014

MT87 Digital Clamp Multimeter Hands On

When you want to measure power/current on electrical device, a kill-a-watt is the easiest method, but it’s not always possible for items like air conditioner, water pumps, etc… because they may simply be no plug to disconnect. Luckily, current clamps are made just for this purpose, where you simply place one of the two wires in a clamp / loop, and it magically measures the current. You can’t put both wires inside the loop or measurement will not work at all. The good news is that such devices are very inexpensive, and I bought MT87 digital clamp multimeter, which is also a multimeter adding voltage and resistance measurement capability, for just $11.33 on DealExtreme. MT87 comes with measurement leads (voltage/resistance only), and a user’s manual. The linked user’s manual is not exactly the same document, but very similar, and also refers to MT87C model which adds temperature measurement. There are […]

January 9, 2026

Home Assistant-compatible Makerfabs ESP32-S3-based energy meter features BL0942 energy metering IC

The Energy Meter for Home Assistant is an ESP32-S3-based single-phase energy monitoring and control module designed to work with Home Assistant via ESPHome. It measures real-time power and energy consumption and also has a remote on/off control. The device is built around the BL0942 calibration-free energy metering IC, which supports voltage, current, power, and energy measurements with less than 1% error. It operates directly from AC 100–240V, includes an onboard 15A relay for switching loads, and provides electrical isolation for safety. Connectivity is done through USB and Wi-Fi using ESPHome for easy firmware flashing, API encryption, and automatic discovery in Home Assistant. These features make it suitable for smart homes, DIY energy monitoring, smart sockets, home energy dashboards, and automation projects. Energy Meter for Home Assistant specifications: Core module – Espressif Systems ESP32-S3-WROOM-1 SoC – ESP32-S3 CPU – Dual-core Tensilica LX7 up to 240 MHz with vector extension for AI/ML workloads […]

Raspberry Pi 5 IPEM Power Energy Monitor

January 14, 2025

Ditronix’s IPEM PiHat turns your Raspberry Pi into a mains power energy monitor (Crowdfunding)

The IPEM PiHat is a HAT (Hardware Attached on Top) board for the Raspberry Pi that turns the single-board computer into a mains power energy monitor with four CT clamps. It provides an accurate way to track energy usage in home, office, and solar energy systems and is compatible with single-phase, two-phase, and three-phase electrical systems. The Raspberry Pi-based power energy monitor uses CT (current transformer) cable clamps to sample and measure data which can be used to report and analyze electric energy usage. This data can be used to save and divert energy to reduce costs and inefficiencies. The system is easy to set up and does not require a professional electrician. It uses a CT current clamp clipped over the building’s main power cables and connected to the local mains circuit for voltage and frequency measurement. The add-on board comes in two variants: IPEM PiHat and IPEM PiHat […]

Creality Falcon T1 5-in-1 Laser Engraver review

August 1, 2026August 4, 2026

Creality Falcon T1 review – A 5-in-1 modular laser engraver tested with 20W fiber and 40W diode laser modules

Creality sent us a sample of the Falcon T1 5-in-1 modular laser engraver for review. The company describes it as the world’s first 5-in-1 laser engraving and cutting machine that supports five types of laser modules in a single unit: 20W diode laser 20W, 40W diode laser, 20w fiber laser, 60W MOPA laser, and 5W UV Laser 5W. The laser heads can be swapped tool-free in just 15 seconds. It works with an HD camera and AI system and can engrave and cut a wide range of materials including wood, leather, acrylic, metal, glass, crystal, and plastic. Diode laser modules are ideal for cutting and engraving wood, leather, and acrylic, the fiber laser module is better suited for marking and engraving metal, the MOPA laser module supports color marking on metals such as stainless steel and titanium, and the UV laser module uses cold processing for high-precision work on glass, […]

Beelink EQi Wildcat Lake mini PC Ubuntu 26.04 review

July 19, 2026

Beelink EQi 304 review – Part 3: Ubuntu 26.04 on a Wildcat Lake mini PC

After checking out the hardware with an unboxing and a teardown of the Beelink EQi Wildcat Lake mini PC, we reviewed the Intel Core 3 304 computer with Windows 11 in detail. We’ve now had time to test the Beelink EQi mini PC running Ubuntu 26.04 with Linux 7.0/7.1 kernels. We’ll report our experience with feature testing, benchmark results, 2.5GbE, 10GbE, and WiFi 6 networking evaluation, storage and USB/Thunderbolt tests, and more, including power consumption measurements. Ubuntu 26.04 installation and system information I’d usually resize the Windows partition to install Ubuntu alongside it in dual boot configuration. However, since the Beelink EQi mini PC also comes with two PCIe Gen4 x1/x2 sockets, I installed Ubuntu 26.04 on a 256GB NVMe (PCIe Gen3 x4) SSD fitted into the PCIe x2 socket and left the Windows 11 partition on the UFS storage alone. Despite the Intel Core 3 304 chip being a […]