A multi-PCB setup to drive a CRT vector monitor

Color Vector Display Controller Brings Arcade Classics Back To Life

May 26, 2022 by Robin Kearey 12 Comments

If you’ve been reading Hackaday long enough, you’ve probably come across a few hacks where someone made simple animations or even video games on an analog oscilloscope screen. Those hacks generally use vector graphics, where the cathode ray tube’s electron beam directly draws geometric shapes onto the screen. This gives the image a unique look that’s quite distinct from the pixel-based raster displays used on TVs and most computer monitors.

Vector displays were also used in several arcade machines of the early 1980s, including classics like Tempest, Gravitar and Star Wars. In order to emulate these games more faithfully than would be possible on a raster monitor, [Robin Champion] designed the vstcm: a color vector monitor controller to easily drive RGB vector monitors.

The design is based on [Trammell Hudson] and [Adelle Lin]’s v.st system, and therefore features a Teensy microcontroller as well as a couple of digital-to-analog converters. While the v.st can only connect to monochrome X/Y systems like oscilloscopes, the vstcm can work with RGB monitors to allow near-perfect emulation of color vector-based games. A custom software interface connects the vstcm to AdvanceMAME, a special version of the well-known arcade emulator that facilitates the connection of unusual display systems.

The end result definitely looks the part, although [Robin] notes that performance is not at the level it could be and requests those familiar with the Teensy platform to help optimize the code. If you’d like to build the vstcm but can’t find a vector monitor, you can always modify the yoke of a conventional CRT. Want to learn more about vector displays? Check out this thorough introduction.

The 512 Gigabyte Floppy Disk

May 26, 2022 by Jenny List 79 Comments

There are times when a technology goes almost overnight as if in a puff of smoke, and others when they fade away gradually over time to the point at which their passing is barely noticed. So it is with removable media, while we still have the occasional USB flash disk or SD card , they do not come anywhere near the floppies, Zip disks, and CD-ROMs of the past in their numbers or ubiquity. If the floppy disk is just a save icon to you there’s still the chance to experience their retro charm though, courtesy of [Franklinstein]. He’s made a 3.5″ floppy disk that eschews 720 k, 1.44 M, or even 2.88 Mb, and goes all the way with a claimed 512 Gb capacity. We’re sure we can’t remember these from back in the day!

Of course as we can see in the video below he’s achieved neither an astounding feat of data compression nor a bleeding-edge method of storing bits in individual iron oxide molecules. Instead the floppy hinges open, and there’s a holder for micro SD cards where the disk itself would be. It’s a bit of fun, and we have to agree with him that it makes a very handy holder for micro SDs that can carry that much data. This sets us wondering though, whether it would be possible to somehow multiplex 14 micro SDs to a microcontroller on a PCB that could fit in a floppy shell. Perhaps an ESP32 could be a slow file server through a web interface?

He makes the point that 512 Gb of floppies would comfortably exceed the height of the tallest buildings were they stacked together, so at the very least this represents a space saving. If you’re looking for something slightly more functional and don’t mind modifying the drive, there’s always this classic approach to marrying a floppy with an SD card.

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Slow Races On A Pinewood Derby Track Built From Scratch

May 20, 2022 by Lewin Day 18 Comments

Pinewood derby racing is a popular pastime for scouting groups and many others besides. [Mr Coster] whipped up his own track with the assistance of some 3D printed parts, and used it to run a competition with a fun twist on the usual theme.

The track starts with a pair of MDF panels, on to which some strips are placed to act as guides for the racers. There’s also a release mechanism built with hinges and a pair of dowels that ensures both racers start the competition at exactly the same time. To give the track a nice transition from the downward slope to the horizontal, a series of curved transition pieces were designed in Fusion 360, 3D printed, and added to the course.

As for the competition, [Mr Coster] decided to eschew the usual focus on outright speed. Instead, students were charged with building the slowest possible car that could still complete the course. Just for the fun of it, though, the kids were then given one day to modify their slowest cars to compete in a more typical fastest-wins event. It gives the students a great lesson in optimizing for different performance parameters.

You might be old-school, though, and want to ruin the fun by taking it all way too seriously. Those competitors may wish to consider some of the advanced equipment we’ve featured before. Alternatively, you could run a no-holds-barred cheater’s version of the contest. Video after the break.

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MiniDisc Player Supports Full Data Transfer

May 14, 2022 by Bryan Cockfield 28 Comments

Between the era of the CD and the eventual rise and domination of streaming music platforms, there was a limbo period of random MP3 players mixed in with the ubiquitous (and now officially discontinued) iPod. In certain areas, though, the digital music player of choice was the MiniDisc, a miniature re-writable CD player with some extra digital features. Among them was the ability to transfer music to the discs over USB, but they did not feature the ability to transfer the songs back to a computer. At least until now, thanks to this impressive hack from [asivery].

Although it sounds straightforward, this trick has a lot of moving parts that needed to come together just right. The MiniDisc player uses a proprietary encoding format called ATRAC, so a codec is needed for that. The MiniDisc player stores data from the disc in a 40-second buffer when playing, so the code reads the data directly from DRAM in 40-second chunks, moves the read head, repeats the process as needed, then stitches the 40-second parts back together. It can work on any Sony NetMD portable, if you are lucky enough to still have one around.

The project is a tremendous asset to the MiniDisc community, especially since the only way to recover data from a MiniDisc player prior to this was to use a specific version known as the RH-1. As [asivery] reports, used RH-1 players are going for incredibly high prices partially because of this feature. Since this new method demonstrates that it’s possible to do with other devices, perhaps its reign in the MiniDisc world will come to a close. For those still outside the loop on this esoteric piece of technology, take a look at this MiniDisc teardown.

Thanks to [Maarten] for the tip!

Framework Board Gets This Round Display PC Rolling

May 10, 2022 by Tom Nardi 15 Comments

The Framework laptop is already a very exciting prospect for folks like us — a high-end computer that we can actually customize, upgrade, and repair with the manufacturer’s blessing? Sounds like music to our ears. But we’re also very excited about seeing how the community can press the modular components of the Framework into service outside of the laptop itself.

A case in point, this absolutely gorgeous retro-inspired computer built by [Penk Chen]. The Mainboard Terminal combines a Framework motherboard, five inch 1080 x 1080 round LCD display, and OLKB Preonic mechanical keyboard into a slick 3D printed enclosure that’s held together with magnets for easy access. Compared to the Raspberry Pi that we usually find tucked into custom computer builds like this, the Framework board offers incredible performance, not to mention the ability to run x86 operating systems and software.

[Penk] has Ubuntu 22.04 LTS loaded up right now, and he reports that everything works as expected, though there are a few xrandr commands you’ll need to run in order for the system to work properly with the circular display. The standard Ubuntu UI doesn’t look particularly well suited to such an unusual viewport, but we imagine that’s an issue you’ll have to learn to live with when experimenting with such an oddball screen.

It was just a few weeks ago that we brought you word that Framework was releasing the mechanical drawings for their Mainboard module, and we predicted then that it would be a huge boon to those building bespoke computers. Truth be told we expected a cyberdeck build of some sort to be the first one to hit our inbox, but you certainly won’t catch us complaining about seeing more faux-vintage personal terminals.

DIY Metal Detector Gives You The Mettle To Find Some Medals

May 2, 2022 by Bryan Cockfield 23 Comments

Hurricane season is rapidly approaching those of us who live in the northern hemisphere. While that does come with a good deal of stress for any homeowners who live in the potential paths of storms it also comes with some opportunities for treasure hunting. Storms tend to wash up all kinds of things from the sea, and if you are equipped with this DIY metal detector you could be unearthing all kinds of interesting tchotchkes from the depths this year.

The metal detector comes to us from [mircemk] who is known for building simple yet effective metal detectors. Unlike his previous builds, this one uses only a single integrated circuit, the TL804 operational amplifier. It also works on the principle of beat-balance which is an amalgamation of two unique methods of detecting metal. When the wire coils detect a piece of metal in the ground, the information is fed to an earpiece through an audio jack which rounds out this straightforward build.

[mircemk] reports that this metal detector can detect small objects like coins up to 15 cm deep, and larger metal objects up to 50 cm. Of course, to build this you will also need the support components, wire, and time to tune the circuit. All things considered, though it’s a great entryway into the hobby.

Want to learn more about metal detecting? Check out this similar-looking build which works on the induction balance principle.

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Hard(er) Drives: Impractical, Slow, Amazing, And Incredible

April 22, 2022 by Ryan Flowers 19 Comments

Computer memory is a problem that has been solved for many years. But early on, it was more than just a small problem. We’ve many of the different kinds at Hackaday over the years, and we’ll link to some of them later on. But one of the original types of memory was called Delay Line memory, which worked by waiting for a signal to propagate slow enough through a device that it was essentially stored in the device. This was highly inefficient, but still a neat concept- one that [Tom7] has taken to entirely new levels of amazing and impractical as seen in the video below the break.

Such factors as “harm to society” are artfully considered

Starting with a demonstration of orbiting chainsaws, he then moves on to explaining how radio propagation waves could be used to temporarily store data while it’s in transit. He missed the opportunity to call it cloud storage, but we’ll forgive him. Extrapolating that further, he decided to use the Entire Internet to store data without its permission, utilizing large ICMP packets and even making it available as block storage in Linux.

Not content to use the entire Internet to store a few kb of data, he moved on to several thousand virtualized NES game systems which are all playing “an inventory management survival horror game” commonly known as Tetris. [Tom7] deconstructs Tetris, analyzing its Random Number Generator, gaming the system to store data in virtual NES consoles by the thousands. What data did he store? The source code to Tetris for the NES. And what did he do with it? Well, he mounted it and ran the program, of course!

The last Harder Drive we’ll leave for those who want to watch the video, because it’s a bit on the “ewww gross!” side of things but is also a bit less successful due to some magic smoke being released.

If none of these things we’ve mentioned were enough, then watch the video for an excellent breakdown of the cost, efficiency, and even the harm to society. For fun, he also tosses blockchain into the mix to see how it fares against the Harder Drives. There’s also at least one easter egg in the video, and the whimsical discussion of engineering is both entertaining and inspiring. How would you implement a Harder Drive?

[Tom7] also gives you the opportunity to follow along with the fun and mayhem by making much of the code available for your perusal. For more fun reading, check out this walk down computer memory lane that we covered last year, as well as a look into Acoustic Delay Line memory.

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