Swap The Clock Chip On The Mac SE/30 With An ATTiny85

As [Phil Greenland] explains in the first part of his excellent write-up, the lithium battery used to keep the real-time clock (RTC) going on the Macintosh SE/30 has a nasty habit of exploding and leaking its corrosive innards all over the board. Looking to both repair the damage on a system that’s already had a battery popped and avoid the issue altogether on pristine boards, he started researching how he could replace the battery with something a bit more modern.

Damage from a ruptured RTC battery.

It turns out, the ATtiny85 is pin-compatible with the Mac’s original RTC chip, and indeed, [Andrew Makousky] had already written some code that would allow the microcontroller to emulate it. This is actually a bit more complex than you might realize, as the original RTC chip was doing double-duty: it also held 256 bytes of parameter random access memory (PRAM), which is where the machine stored assorted bits of info like which drive to boot from and the mouse cursor speed.

But after getting the mod installed, the computer refused to start. It turns out the project targeted earlier machines like the Macintosh Plus and SE, and not his higher-performance SE/30. Thanks to community resources like this KiCad recreation of the SE/30’s motherboard, contemporary technical documents, and his trusty logic analyzer, [Phil] was able to figure out that the timing was off — the code was simply struggling to respond to the faster machine. Continue reading “Swap The Clock Chip On The Mac SE/30 With An ATTiny85”

A blue enclosure with "IoT AI-assisted Deep Algae Bloom Detector w/Blues Wireless" written on the front. Two black cables run over a wooden desk to a cylinder with rocks on the bottom and filled with murky water. A bookshelf lurks in the background.

Detecting Algal Blooms With The Help Of AI

Harmful Algal Blooms (HABs) can have negative consequences for both marine life and human health, so it can be helpful to have early warning of when they’re on the way. Algal blooms deep below the surface can be especially difficult to detect, which is why [kutluhan_aktar] built an AI-assisted algal bloom detector.

After taking images of deep algal blooms with a boroscope, [kutluhan_aktar] trained a machine learning algorithm on them so a Raspberry Pi 4 could recognize future occurrences. For additional water quality information, the device also has an Arduino Nano connected to pH, TDS (total dissolved solids), and water temperature sensors which then are fed to the Pi via a serial connection. Once a potential bloom is spotted, the user can be notified via WhatsApp and appropriate measures taken.

If you’re looking for more environmental sensing hacks, check out the OpenCTD, this swarm of autonomous boats, or this drone buoy riding the Gulf Stream.

An E-Ink Progress Bar For Your Unborn Child

Having a child is a major milestone in a person’s life, and there’s a long list of things to get done before that little bundle of joy kicks and screams its way into the world. What better way to make sure you’ve still got time to paint the nursery and assemble the crib than to have an automated loading screen that shows just how far along the organic 3D printing process is?

This fetal development tracker was put together by [mokas] using Adafruit’s ESP32-S2 powered MagTag. As the name implies, the all-in-one electronic ink development board is designed so that it can be adhered to a metallic surface with integrated magnets. The idea is that you can pop a battery in the low-power device, stick it on your refrigerator, and have a regularly updated display of…well, whatever you want. Continue reading “An E-Ink Progress Bar For Your Unborn Child”

Arduino Library Brings Rtl_433 To The ESP32

If you have an RTL-SDR compatible radio there’s an excellent chance you’ve heard of the rtl_433 project, which lets you receive and decode signals from an ever-expanding list of supported devices in the ISM radio bands. It’s an incredibly useful piece of software, but the fact that it requires an external software defined radio and a full-fledged computer to run dictated the sort of projects it could realistically be used for.

But thanks to the rtl_433_ESP Arduino library developed by [NorthernMan54], we’re now able to pack that functionality into a much smaller package. All you need is an ESP32 microcontroller and a CC1101 or SX127X transceiver module. If you’re looking for a turn-key hardware platform, the documentation notes the LILYGO LoRa32 V2 board includes the required hardware, plus adds a handy OLED display and microSD slot. It should be noted that the range of these radios don’t compare particularly well to a full-size RTL-SDR device, but that probably won’t come as much of a surprise. Continue reading “Arduino Library Brings Rtl_433 To The ESP32”

DIY Fiber Laser Adds Metal Cutting To The Mix

Sadly, the usual CO2-powered suspects in the DIY laser cutter market are woefully incapable of cutting metal. Sure, they’ll cut the heck out of plywood and acrylic, and most will do a decent job at engraving metal. But cutting through a sheet of steel or aluminum requires a step up to much more powerful fiber laser cutters. True, the costs of such machines can be daunting, but not daunting enough for [Travis Mitchell], who has undertaken a DIY fiber laser cutter build that really caught our eye.

Right off the bat, a couple of things are worth noting here. First — and this should be obvious from the fountains of white-hot sparks in the video below — laser cutters are dangerous, and you should really know what you’re doing before tackling such a build. Second, just because [Travis] was able to cut costs considerably compared to a commercial fiber laser cutter doesn’t mean this build was cheap in absolute terms — he reports dropping about $15,000 so far, with considerable ongoing costs to operate the thing.

That said, there doesn’t appear to be anything about this build that anyone with some experience building CNC machines wouldn’t be able to tackle. The CNC side of this is pretty straightforward, although we note that the gantry, servos, and controller seem especially robust.

The laser itself is an off-the-shelf machine, a Raycus RFL-C1000 fiber laser and head that packs a 1,000-Watt punch. There’s also the required cooling system for the laser, and of course there’s an exhaust system to get rid of the nasty fumes.

All that stuff requires a considerable investment, but we were surprised to learn how much the consumables cost. [Travis] opted for bottled gas for the cutter’s gas assist system — low-pressure oxygen for carbon steel and high-pressure nitrogen for everything else. Refills are really pricey, in part because of the purity required, but since the proper compressor for the job is out of the budget for now, the tanks will have to do. And really, the thing cuts like a dream. Check out the cutting speed and precision in the video below.

This is but the first in a series of videos that will detail the build, and if [Travis] thought this would whet our appetites for more, he was right. We really haven’t seen many DIY fiber laser builds, but we have seen a teardown of a 200-kW fiber laser that might tickle your fancy.

Continue reading “DIY Fiber Laser Adds Metal Cutting To The Mix”

A Medieval Gothic Monastery Built Using CAD / CAM

Just because you’re a monk doesn’t mean you can’t use CAD. The Carmelite monks of Wyoming are building a grandiose Gothic Monastery, and it’s awe inspiring how they are managing to build it.

The Carmelite monks needed a new, larger monastery to house their growing numbers, and found a parcel of land near Meeteetse Creek in Wyoming. The design of their new Gothic monastery was outsourced to an architectural firm. Gothic architecture is characterised by key architectural elements such as pointed arches, large stained glass windows, rib vaults, flying buttresses, pinnacles and spires, elaborate entry portals, and ornate decoration.

After some research, the monks settled on using Kansas Silverdale limestone for the monastery. Cutting and carving the elaborate stone pieces required for such a project, within time and cost constraints, could only be achieved using CNC machines. Hand carving was ruled out as it was a very slow process, would cost a whole lot more, and it wouldn’t be easy to find the artisans for the job. So when it came to shortlisting vendors for the vast amount of stone cutting and carving required for construction, the monks found themselves alarmed at how prohibitively expensive it would turn out to be.

Continue reading “A Medieval Gothic Monastery Built Using CAD / CAM”

Hackaday Podcast 201: Faking A Transmission, Making Nuclear Fuel, And A Slidepot With A Twist

Even for those with paraskevidekatriaphobia, today is your lucky day as Editor-in-Chief Elliot Williams and Staff Writer Dan Maloney sit under ladders with umbrellas while holding black cats to talk about the week in awesome hacks. And what a week it was, with a Scooby Doo code review, mushrooms in your PCBs, and the clickiest automatic transmission that never was. Have you ever flashed the firmware on a $4 wireless sensor? Maybe you should try. Wondering how to make a rotary Hall sensor detect linear motion? We’ll answer that too. Will AI muscle the dungeon master out of your D&D group? That’s a hard no. We’ll talk about a new RISC-V ESP32, making old video new again, nuclear reactor kibble, and your least satisfying repair jobs. And yes, everyone can relax — I’m buying her a new stove.

Download the podcast in case our servers get unlucky.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Continue reading “Hackaday Podcast 201: Faking A Transmission, Making Nuclear Fuel, And A Slidepot With A Twist”