A Great Resource For The Would-Be Pinball Machine Builder

April 29, 2022 by Dave Rowntree 12 Comments

Those of us beyond a certain age will very likely have some fond memories of many an hour spent and pocket money devoured feeding the local arcade pinball machine. At one time they seemed to be pretty much everywhere, but sadly, these days they seem to have largely fallen out of favour and are becoming more of speciality to be specifically sought out. Apart from a few random ones turning up — there’s a fun Frankenstein-themed machine in the Mary Shelley Museum in Bath, England — a trip to a local amusement arcade is often pretty disappointing, with modern arcade machines just not quite scratching that itch anymore, if you ask us. So what’s an old-school hacker to do, but learn how to build a machine from scratch, just the way we want it? A great resource for this is the excellent Pinball Makers site, which shows quite a few different platforms to build upon and a whole ton of resources and guides to help you along the way.

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Polar Planimeter Quantifies Area By Plotting Perimeter

March 25, 2022 by Ryan Flowers 12 Comments

These days it’s hard to be carry the label “maker” or “hacker” without also being proficient in some kind of CAD- even if the C is for Cardboard. But before there was CAD there was Drafting and its associated arts, and one couldn’t just select a shape and see its area in the square unit of your choice. So how could an old school draftsman figure out the area of complex shapes? [Chris Staecker] introduces us to the polar planimeter, a measuring tool created specifically for the purpose and explained in full in the video below the break.

The polar planimeter being discussed is a higher end unit from the 1960’s. Interestingly, the first polar planimeters were invented in the early 19th century even before the math that describes their function was completed. A lever is placed in a fixed position on one end and into the planimeter on the other. The planimeter itself has another arm with a reticle on it. The unit is zero’d out with a button, and the outline of the shape in question is traced in a clockwise fashion with the reticle.

What makes the polar planimeter capable of measuring in multiple dimensions is the fixed arm. The fixed arm pivots around, allowing the planimeter to track angle changes which affects the output. So, the planimeter isn’t just measuring the length of the perimeter, but the size of the perimeter. The final measurement is output in square inches.

Overall it’s a really slick tool we didn’t know existed, and it’s fascinating to see how such problems were solved before everything could be done with a mouse click or two. Be sure to check out this 100+ year old reference set to round out your knowledge of past knowledge. Thanks to [Zane] for the great tip!

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Retro Breadboard Gives Up Its 1960s Secrets

March 13, 2022 by Dan Maloney 18 Comments

When we see [Ken Shirriff] reverse engineering something, it tends to be on the microscopic level. His usual forte is looking at die photos of strange and obsolete chips and figuring out how they work. And while we love those efforts, it’s nice to see him in the macro world this time with a teardown and repair of a 1960s-era solderless breadboard system.

If you’d swear the “Elite 2 Circuit Design Test System” featured in [Ken]’s post looks familiar, it’s probably because you caught his partner-in-crime [CuriousMarc]’s video on the very same unit, an eBay score that arrived in non-working condition. The breadboard, which retailed for $1,300 in 1969 — an eye-watering $10,000 today — was clearly not aimed at the hobbyist market. Truth be told, we didn’t even know that solderless breadboards were a thing until the mid-70s, but live and learn. This unit has all the bells and whistles, including three variable power supplies, an array of switches, buttons, indicator lamps, and jacks for external connections, and a pulse generator as well as a legit function generator.

Legit, that would be, if it actually worked. [Ken]’s contribution to the repair was a thorough teardown of the device followed by reverse-engineering the design. Seeing how this thing was designed around the constraints of 1969 technology is a real treat; the metal can transistor and ICs and the neat and tidy PCB layout are worth the price of admission alone. And the fact that neon lamps and their drivers were cheaper and easier to use than LEDs says a lot about the state of the art at the time.

As for the necessary repairs, [Marc]’s video leaves off before getting there. That’s fine, we’re sure he’ll put [Ken]’s analysis to good use, and we always enjoy [Marc]’s video series anyway. The Apollo flight comms series was a great one, too. Continue reading “Retro Breadboard Gives Up Its 1960s Secrets” →

Screenshot of a 1988 news report on the Morris Worm computer virus

Retrotechtacular: Cheesy 1980s News Report On Early Internet Virus

March 8, 2022 by Drew Littrell 34 Comments

It was a cold autumn night in 1988. The people of Cambridge, Massachusetts lay asleep in their beds unaware of the future horror about to be unleashed from the labs of the nearby college. It was a virus, but not just any virus. This virus was a computer program whose only mission was to infect every machine it could come in contact with. Just a few deft keystrokes is all that separated law abiding citizens from the…over the top reporting in this throwback news reel posted by [Kahvowa].

Computer History Museum exhibit of the floppy disk used to distribute the Morris worm computer virus. — Computer History Museum exhibit featuring the original floppy disk used to distribute the Morris Worm computer virus.

To be fair, the concept of a computer virus certainly warranted a bit of explanation for folks in the era of Miami Vice. The only places where people would likely run into multiple computers all hooked together was a bank or a college campus. MIT was the campus in question for this news report as it served as ground zero for the Morris Worm virus.

Named after its creator, Robert Tappan Morris, the Morris Worm was one of the first programs to replicate itself via vulnerabilities in networked computer systems. Its author intended the program to be a benign method of pointing out holes, however, it ended up copying itself onto systems multiple times to the point of crashing. Removing the virus from an infected machine often took multiple days, and the total damage of the virus was estimated to be in the millions of dollars.

In an attempt to anonymize himself, Morris initially launched his worm program from a computer lab at MIT as he was studying at Cornell at the time. It didn’t work. Morris would go onto to be the first person to receive a felony conviction under the 1986 Computer Fraud and Abuse Act. After the appeals process, he received a sentence a community service and a fine. After college Morris co-founded the online web store software company Viaweb that Yahoo! would acquire in 1998 for 49 million dollars. Years later in an ironic twist, Morris would return to academia as a professor at MIT’s department of Electrical Engineering and Computer Science.

Interested in some info on viruses of a different nature? Check out this brief history on viruses from last year.
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90s PC With Modern Parts Throws Many Off Track

February 24, 2022 by Bryan Cockfield 17 Comments

When building a desktop computer, usually the budget is the limiting factor. Making sacrifices on one part in order to improve another without breaking the bank is part of the delicate balance of putting together a capable PC. If you’re lucky enough to have the sponsors that [Shank] has though, caution can be thrown to the wind with regards to price for some blisteringly fast parts. Putting them in a ’90s Hot Wheels case to build the ultimate sleeper PC, though, is just icing on the top.

This isn’t quite as simple as replacing a motherboard in a modern PC case, though. The Hot Wheels PC used a mini-ITX standard and is quite a bit smaller than most modern computers outside of something like a Mac Mini. To get the RTX 3060 GPU into the computer the shrouds needed to be removed to save space, plus an unusual 92mm form factor liquid CPU cooler needed to be installed. An equally obscure power supply was included to round out the Ryzen 9 build and after a lot of tinkering eventually all the parts were fitted into this retro case including the original, working floppy disk drive. After that some additional case modding was installed such as RGB lighting, wheels with spinning rims, a spoiler, and an exhaust pipe.

The main issue with this build was temperatures, and both the CPU and GPU were topping out at dangerously high temperatures until [Shank] installed a terrifying 11,000 RPM case fan. With a series of original CRT monitors to go along with this sleeper PC he can have up to 9 displays with surprisingly high video quality thanks to the fundamental properties of CRTs. The video is definitely worth a watch and falls right in line with some of [Shank]’s other console mods that he is famous for such as this handheld Virtual Boy.

Thanks to [Fast Rock Productions] for the tip!

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Commodore 64 Monitor Traces I/O Calls, Eases Debugging

February 18, 2022 by Donald Papp 7 Comments

Developing for the Commodore 64 can be a rewarding retrocomputing experience, and thanks to [Dave Van Wagner], things are easier with his C64 IO_Monitor project, which opens the door to logging and tracing Kernal I/O calls for closer inspection. That’s not a typo, by the way. Kernal is what handles the C64’s low-level OS routines. Amusingly, as the story goes, it did in fact originate as a misspelling of kernel, but the name stuck.

What [Dave]’s program does is trace and log all input and output calls going through Kernal, which includes just about any function one might imagine. Things like keyboard input, screen output, and disk or tape I/O are all dutifully counted and logged, allowing one to really peek under the hood at a low level when doing any kind of development work. This kind of tool has turned out to be pretty handy given [Dave]’s penchant for porting Commodore emulators to a variety of (sometimes unusual) platforms.

Interested in giving it a spin? Head to the project’s GitHub repository for all the necessary files as well as some usage details, and enjoy making debugging and development a little less opaque than it otherwise would be.

Featured image of Aladdin's Castle Arcade

Retrotechtacular: Raw Video From Inside A 1980s Arcade

February 14, 2022 by Drew Littrell 42 Comments

It was just this year that Sega left the arcade business for good. A company synonymous with coin-op games for over a half century completely walked away from selling experiences you can only get on location. No more Outrun or Virtua Fighter machines, because arcades these days tend to resemble The House of the Dead. Arcades still exist to a degree, it’s just that headlines like that serve only as a reminder of an era gone by. Which is what makes raw footage like the video [Jon] posted of an Aladdin’s Castle arcade from the 1980s so compelling.

scan of Aladdin's Castle Arcade pamphlet ad — Aladdin’s Castle ad brochure circa 1983. Credit: John Andersen

The raw VHS footage starts with a sweep around the location’s pinball machines and arcade cabinets. There’s an extended shot of a rare TX-1 tri-monitor sitdown cabinet. The racing game was the first of its kind to feature force feedback in the steering wheel, so it’s no wonder it received the focus. The arcade’s lighting tech was also a point of pride as it allowed for programmable lighting cues. A far cry from the flickering fluorescent tubes no doubt in use elsewhere. Eventually the employee filming takes us to the back room where it the owner has made it abundantly clear that they are not a fan of Mondays, judging by the amount of Garfield merchandise.

Bally’s Aladdin’s Castle was a chain of arcades and had nearly 400 locations across the US at its height in the mid 1980s (at least according to their brochure seen above). Those neon red letters were a mainstay of American shopping malls throughout the decade. Namco, the Pac-Man people, acquired Aladdin’s Castle in 1993 and the brand faded away soon after. Although there is a lone location in Quincy, IL that is still open for business today.

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