Rewinding A Car Alternator For 240 Volt

Two phases installed on the stator. (Credit: FarmCraft101, YouTube)
Two phases installed on the stator. (Credit: FarmCraft101, YouTube)

As part of his quest to find the best affordable generator for his DIY hydroelectric power system, [FarmCraft101] is trying out a range of off-the-shelf and DIY solutions, with in his most recent video trying his hands at the very relaxing activity of rewiring the stator of an alternator.

Normally car alternators output 12VDC after internal rectification, but due to the hundreds of meters from the turbine to the shed, he’d like a higher voltage to curb transmission losses. The easiest way to get a higher voltage out of a car alternator is to change up the wiring on the stator, which is definitely one of those highly educational tasks.

Disassembling an alternator is easy enough, but removing the copper windings from the stator is quite an ordeal, as they were not designed to ever move even a fraction of a millimeter after assembly.

With that arduous task finished, the rewinding was done using 22 AWG copper enamel wire, compared to the original 16 AWG wire, and increasing the loops per coil from 8 to 30. This rewinding isn’t too complicated if you know what you’re doing, with each coil on each of the three windings placed in an alternating fashion, matching the alternating South/North poles on the rotor.

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How Resident Evil 2 For The N64 Kept Its FMV Cutscenes

Originally released for the Sony PlayStation in 1998, Resident Evil 2 came on two CDs and used 1.2 GB in total. Of this, full-motion video (FMV) cutscenes took up most of the space, as was rather common for PlayStation games. This posed a bit of a challenge when ported to the Nintendo 64 with its paltry 64 MB of cartridge-based storage. Somehow the developers managed to do the impossible and retain the FMVs, as detailed in a recent video by [LorD of Nerds]. Toggle the English subtitles if German isn’t among your installed natural language parsers.

Instead of dropping the FMVs and replacing them with static screens, a technological improvement was picked. Because of the N64’s rather beefy hardware, it was possible to apply video compression that massively reduced the storage requirements, but this required repurposing the hardware for tasks it was never designed for.

The people behind this feat were developers at Angel Studios, who had 12 months to make it work. Ultimately they achieved a compression ratio of 165:1, with software decoding handling the decompressing and the Reality Signal Processor (RSP) that’s normally part of the graphics pipeline used for both audio tasks and things like upscaling.

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Teardown Of An Apple AirTag 2 With Die Shots

There are a few possible ways to do a teardown of new electronics like the Apple AirTag 2 tracker, with [electronupdate] opting to go down to the silicon level, with die shots of the major ICs in a recent teardown video. Some high-resolution photos are also found on the separate blog page.

First we get to see the outside of the device, followed by the individual layers of the sandwiched rings of the device, starting with the small speaker, which is surrounded by the antenna for the ultrawide band (UWB) feature.

Next is the PCB layer, with a brief analysis of the main ICs, before they get lifted off and decapped for an intimate look at their insides. These include the Nordic Semiconductor nRF52840 Bluetooth chip, which also runs the firmware of the device.

The big corroded-looking grey rectangle on the PCB is the UWB chip assembly, with the die shot visible in the heading image. It provides the localization feature of the AirTag that allows you to tell where the tag is precisely. In the die analysis we get a basic explanation of what the structures visible are for. Basically it uses an array of antennae that allows the determination of time-of-flight and with it the direction of the requesting device relative to it.

In addition to die shots of the BT and UWB chips we also get the die shot of the Bosch-made accelerometer chip, as well as an SPI memory device, likely an EEPROM of some description.

As for disabling the speaker in these AirTag 2 devices, it’s nestled deep inside, well away from the battery. This is said to make disabling it much harder without a destructive disassembly, yet as iFixit demonstrated, it’s actually fairly easy to do it non-destructively.

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Hackaday Links: February 1, 2026

For many readers, more snow is the last thing they want to see right now…but what if it comes in the form of an online simulator in the style of an old DOS game? Created by [Potch], it works like one of those “falling sand” simulators, with sliders that let you control various elements of the wintry action. For more a immersive experience, open the window and let some cold air in while you play.

If those old school graphics have you yearning for a simpler time, then you’ll love Places to Telnet, a page on the very slick CRT-themed telnet.org that lists servers you can connect to. The list is made up primarily of games, but there’s also systems you can call up to do things like show the weather or browse Wikipedia. They even take submissions, so if you know any interesting destinations that aren’t on the list, make sure to share with the class.

Our ability to make and use tools is one of the things that separates us from the rest of the animal kingdom, and is an ability not often seen outside of primates. But a recent paper in Current Biology describes how one cow, Veronika, has been observed using a long-handled brush to scratch herself. Apparently the clever heifer will even flip the brush around and use the handle side when she wants to really dig in there. The paper says the findings “invite a reassessment of livestock cognition”, and points out that little serious research has been done on bovine intelligence in the 10,000 or so years since humans first domesticated them. We’re just happy this paper came out when it did — that way it will be a distant memory by the time we fire up the grill in the summer.

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FLOSS Weekly Episode 862: Have Your CAKE And Eat It Too

This week Jonathan chats with Toke Hoiland-Jorgensen about CAKE_MQ, the newest Kernel innovation to combat Bufferbloat! What was the realization that made CAKE parallelization? When can we expect it in the wild? And what’s new in the rest of the kernel world? Watch to find out!

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Make Your Own ESP32-Based Person Sensor, No Special Hardware Needed

Home automation with high usefulness and low annoyance tends to rely on reliable person sensing, and [francescopace]’s ESPectre shows one way to do that cheaply and easily by leveraging hardware that’s already present on a common dev board.

ESPectre is an ESP32-based open source motion detector that detects movement without any cameras or microphones. It works similarly to millimeter-wave (mmWave) radar motion detectors in the sense that when a person moves, wireless signals are altered slightly as a result. ESPectre can detect this disturbance by watching and analyzing the Wi-Fi channel state information (CSI) and doing some very smart math and filtering. It’s cheap, easy to deploy and use, and even integrates with Home Assistant.

Combining a sensor like this with something else like a passive infrared (PIR) motion sensor is one way to get really robust results. But keep in mind that PIR only senses what it can see, whereas ESPectre works on WiFi, which can penetrate walls.

Since ESPectre supports low-cost ESP32 variants and is so simple to get up and running, it might be worth your time to give it a trial run. There’s even a browser-based ghost-dodging game [francescopace] put online that uses an ESPectre board plugged in over USB, which seems like a fun way to get a feel for what it can do.

Restoring A 1924 Frigidaire B-9 Refrigerator Back To Working Condition

Before the refrigerator became a normal part of any kitchen, those with enough money to throw around could get an icebox, which used melting ice to cool food and drinks in a second compartment. As refrigerators became available for sale in the 1920s, this created somewhat awkward transition models, like the 1924 Frigidaire B-9 that [David Allen] recently got offered for a restoration. This was part of the restoration of a 1926 house, which foresaw putting this venerable unit back into operation.

As [David] explains, this refrigerator was still in use until about 1970 when it broke down, and repairs proved tricky. Clearly, the fault wasn’t that severe as [David] got it working again after a number of small repairs and a lot of maintenance. The running unit with its basic elements can be seen purring away in the completion video, with the journey to get there covered in a video series starting with the first episode.

What’s fascinating is that during this aforementioned transition period, the vapor compression electric cooling system was an optional extra, meaning that the basic layout is still that of an icebox. Correspondingly, instead of ice in the ice compartment, you find the low-side float evaporator, with the basement section containing the condensing unit, motor, and compressor. The temperature sensor is also a miracle of simplicity, using bellows that respond to the temperature and thus volume of the evaporator coolant, which trigger a switch that turns on the compressor.

Despite a hundred years having passed since this refrigerator was constructed, at its core it works exactly the same as the unit we have in our kitchens today, albeit with higher efficiency, more electronics, and with the sulfur dioxide refrigerant replaced with something less toxic to us humans.

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