If you predate the pocket calculator, you may remember slide rules. But slide rules take a a little skill to use. There was a market for other devices that were simpler or, in some cases, cheaper. One common one was the “magic brain” or Addiator which was a little metal box with some slots that could add numbers. However, using clever tricks it could also subtract and — in a fashion — multiply. [Our Own Devices] has a teardown of the device you can see in the video below. It is deceptively simple, and the description of how it works is at least as interesting as the peek inside.
We remember these on the market and, honestly, always thought they were simple tally mechanisms. It turns out they are both less and more than that. Internally, the device is a few serrated sheet metal strips in a plastic channel. The subtraction uses a complement addition similar to how you do binary subtraction using 2’s complement math. Multiplication is just repetitive addition, which is fine for simple problems.
Continue reading “Pocket Calculator Isn’t A Brain Or Magic”
The Intel 8088 is an interesting chip, being a variant of the more well-known 8086. Given the latter went on to lend its designation to one of the world’s favorite architectures, you can tell which of the two was higher status. Regardless, it was the 8088 that lived in the first IBM PC, and now, it even has its own open-source BIOS.
As with any BIOS, or Basic Input Output System, it’s charged with handling core low-level features for computers like the Micro 8088, Xi 8088, and NuXT. It handles chipset identification, keyboard and mouse communication, real-time clock, and display initialization, among other things.
Of course, BIOSes for 8088-based machines already exist. However, in many cases, they are considered to be proprietary code that cannot be freely shared over the internet. For retrocomputing enthusiasts, it’s of great value to have a open-source BIOS that can be shared, modified, and tweaked as needed to suit a wide variety of end uses.
If you want to learn more about the 8088 CPU, we’ve looked in depth at that topic before. Feel free to drop us a line with your own retro Intel hacks if you’ve got them kicking around!
These days, it’s possible to buy a number of different Polaroid instant cameras new off the shelf. That’s largely thanks to the retro resurgence that has buoyed interest in everything from vinyl records to analog synthesizers. However, if you’re truly old-school, you might still be rocking a vintage Polaroid SX-70 camera. Thankfully, there’s a way to convert these old rigs to work properly with the more popular modern 600 film.
The interesting thing about the SX-70 camera design is that its shutter speed and aperture setting are essentially linked together as the aperture and shutter assembly are combined into one unit with a variable tear-drop shaped opening. Thus, the timing of the shutter opening and closing and the extent to which it opens are what determines exposure and aperture.
Thankfully, [Jake Bright] has learned a lot about these unique cameras and exactly how this complex system operates. He shares his tips on firstly restoring the camera to factory-grade operation, and then the methods in which they may be converted to work with modern film. Fundamentally, it’s about changing capacitors or resistors to change the shutter/aperture timing. However, do it blindly and you’ll have little success. You first need to understand the camera’s mechanics, pneumatics, and its “Electric Eye” control system before you can get things dialed in just so.
We’ve seldom seen such a great deep dive into a camera outside of full-fat engineering documentation. [Jake] should be commended on his deep understanding and command of these fine instant cameras from yesteryear. May the Polaroid picture never die. Video after the break. Continue reading “Converting A Polaroid SX70 Camera To Use 600 Film”
For all that modern washers and dryers do, they don’t let you know when they’re finished. Or they do, but it’s only a short victory song that plays once and can be easy to miss. What most of us need is a gentle reminder that there’s damp laundry festering in the washer, or fresh laundry in the dryer getting wrinkly.
This laundry monitor from [Sparks and Code] is version 2.0. The first version was working fine, but it was based on vibration (or lack thereof). Fast forward a few years, and [Sparks and Code] got a modern pair that’s so finely tuned, it doesn’t produce enough vibration to register. Back to the drawing board [Sparks and Code] went, and eventually came up with version 2.0.
Now, [Sparks and Code] is detecting whether the machines are on using a pair of split-core transformers to monitor power at the breaker box. With these, you just run the wire through the hole, and it gives the relative mV value going through the wire on a 3.5mm cable. Those cables are connected to an ESP32 inside the 3D-printed box, which is mounted above the cabinet door. Since [Sparks and Code] already has home assistants all over the house, it was easy to integrate and have them all play the message ‘please flip the laundry’.
Once this project was all buttoned up, they thought of one issue — the self-cleaning cycle. Since it takes about four hours, they like to run it overnight. You can see the problem here — no one wants to hear Alexa at 3AM. Fortunately, [Sparks and Code] was able to adjust the Python script to ignore these events. Be sure to check out the build video after the break.
If only the dryer could empty itself and fold the clothes. Oh wait, there’s a robot for that.
Continue reading “Spinning Up A New Laundry Monitor”
This may look like another DIY mechanical keyboard, but it’s hiding a secret. [Mx. Jack Nelson] has combined Halloween and keyboards in glorious, haunted fashion. Type a line, any line into this bad boy and you get a spooky, sort of cryptic response generated by AI.
Essentially, a Raspberry Pi Pico W does all the work, it handles the keyboard matrix, connects to Wi-Fi, sends the input to ChatGPT, and spits the response out on the screen wherever the cursor happens to be. Incidentally, it turns out [Mx. Jack Nelson] used ChatGPT to generate much of the CircuitPython code.
The layout is a custom 40% that is heavily influenced by the Akko 40%, with the Ctrl, Alt, and Win keys replaced by Ctrl, Cmd, and Opt. This was [Mx. Jack Nelson]’s first PCB, and you never forget your first. You don’t want to miss the demo video after the break.
Are keyboards just not spooky enough for you? Here’s a creepy baby doll that does basically the same thing.
Continue reading “2023 Halloween Hackfest: Haunted Keyboard Is Free From Ghosting”
We were not surprised to read that a company that tracks NFTs declared that most NFTs are now worthless. But the NFT — non-fungible token — market was huge, so around 23 million people invested in NFTs that are now worth nothing. Worse still, the company notes that because of oddities in how NFTs are priced, the real number of worthless assets is probably even greater than they think.
It is easy to look back and think that it was obvious. After all, an NFT of the Mona Lisa isn’t really the Mona Lisa. Nor does owning it confer any real benefit other than “bragging rights” of owning an NFT of the Mona Lisa. But that’s like saying Luke should have known Darth Vader was his father — it’s only evident after the fact. History is replete with bad ideas at the time that paid out down the road. Of course, history is also full of bad ideas that were simply bad ideas. For every Apple or Google stock you didn’t buy at $4 a share, there are a hundred $4 stocks that you shouldn’t have bought.
The NFT craze was sort of a viral event. We usually think of these as part of the Internet culture, but that’s not really true. There is actually very little new on the Internet. The Internet just lets things reach further and faster than before.
Don’t believe me? Kilroy was a viral meme in the 1940s. Fads such as hula hoops, phone booth stuffing, and flagpole sitting were the ice bucket challenges of their day. But, of course, these things weren’t economic. Just fun fads. But economic fads that turn out to be a bad idea are nothing new, either.
Continue reading “NFTs And Tulipmania: A Little Bit Of History Repeating”
Hackaday Editors Elliot Williams and Tom Nardi meet up virtually to talk about the week’s top stories and hacks, such as the fine art of resistor trimming and lessons learned from doing overseas injection molding. They’ll go over circuit bending, self-driving cars, and a solar camera that started as a pandemic project and turned into an obsession. You’ll also hear about Linux on the Arduino, classic ICs etched into slate, and an incredible restoration of one of the most interesting Thinkpads ever made. Stay tuned until the end to hear about a custom USB-C power supply and the long-awaited Hackaday Supercon 2023 Vectorscope badge.
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!
Download your own, unlimited-edition MP3 of this week’s podcast.
Continue reading “Hackaday Podcast Ep 241: Circuit Bending, Resistor Filing, The Butterfly Keyboard, And The Badge Reveal”