Apollo DSKY Display Glows Again

We love seeing old technology brought back to life, especially when it’s done in the context of how the device was originally intended to be used. And double points when it’s space gear, like what [Curious Marc] and his usual merry band of cohorts did when they managed to light up a couple of real Apollo DSKY displays.

The “Display and Keyboard” formed the human interface to the Apollo Guidance Computer, the purpose-built machine that allowed Apollo missions to fly to the Moon, land safely, and return to Earth. Complete DSKYs are hard to come by, but a lucky collector named [Marcel] was able to score a pair of the electroluminescent panels, one a prototype and one a flight-qualified spare. He turned them over to AGC guru [Carl Claunch], who worked out all the details of getting the display working again —  a non-trivial task with a device that needs 250 volts at 800 Hertz.

The first third of the video below mostly concerns the backstory of the DSKY displays and the historical aspects of the artifacts; skip to around the 12:30 mark to get into the technical details, including the surprising use of relays to drive the segments of the display. It makes sense once you realize that mid-60s transistors weren’t up to the task, and it must have made the Apollo spacecraft a wonderfully clicky place. We were also intrigued by the clever way the total relay count was kept to a minimum, by realizing that not every combination of segments was valid for each seven-segment display.

The video has a couple of cameos, like [Ben Krasnow], no slouch himself when it comes to electroluminescent displays and DSKY replicas. We also get a glimpse of well-known component slicer and MOnSter 6502-tamer [TubeTime] too. Continue reading “Apollo DSKY Display Glows Again”

Hackaday Links Column Banner

Hackaday Links: July 18, 2021

Tell the world that something is in short supply, and you can bet that people will start reacting to that news in the ways that make the most sense to them — remember the toilet paper shortage? It’s the same with the ongoing semiconductor pinch, except that since the item in short supply is (arguably) more valuable than toilet paper, the behavior and the risks people are willing to take around it are even more extreme. Sure, we’ve seen chip hoarding, and a marked rise in counterfeit chips. But we’d imagine that this is the first time we’ve seen chip smuggling quite like this. The smuggler was caught at the Hong Kong-Macao border with 256 Core i7 and i9 processors, valued at about $123,000, strapped to his legs and chest. It reminds us more of “Midnight Express”-style heroin smuggling, although we have to say we love the fact that this guy chose a power of 2 when strapping these babies on.

Speaking of big money, let’s say you’ve pulled off a few chip heists without getting caught, and have retired from the smuggling business. What is one to do with the ill-gotten gains? Apparently, there’s a big boom in artifacts from the early days of console gaming, so you might want to start spreading some money around there. But you’d better prepare to smuggle a lot of chips: last week, an unopened Legend of Zelda cartridge for the NES sold for $870,000 at auction. Not to be outdone, two days later someone actually paid $1.56 million for a Super Mario 64 cartridge, this time apparently still in the tamperproof container that displayed it on a shelf somewhere in 1996. Nostalgia can be an expensive drug.

And it’s not just video games that are commanding high prices these days. If you’ve got a spare quarter million or so, why not bid on this real Apollo Guidance Computer and DSKY? The AGC is a non-flown machine that was installed in LTA-8, the “lunar test article” version of the Landing Module (LM) that was used for vacuum testing. If the photos in the auction listing seem familiar, it’s with good reason: this is the same AGC that was restored to operating condition by Carl Claunch, Mike Stewart, Ken Shiriff, and Marc Verdiell. Sotheby’s estimates the value at $200,000 to $300,000; in a world of billionaire megalomaniacs with dreams of space empires, we wouldn’t be surprised if a working AGC went for much, much more than that.

Meanwhile, current day space exploration is going swimmingly. Just this week NASA got the Hubble Space Telescope back online, which is great news for astronomers. And on Mars, the Ingenuity helicopter just keeps on delivering during its “operations demonstration” mission. Originally just supposed to be a technology demonstration, Ingenuity has proven to be a useful companion to the Perseverance rover, scouting out locations of interest to explore or areas of hazard to avoid. On the helicopter’s recent ninth flight, it scouted a dune field for the team, providing photographs that showed the area would be too dangerous for the rover to cross. The rover’s on-board navigation system isn’t great at seeing sand dunes, so Ingenuity’s images are a real boon to mission planners, not to mention geologists and astrobiologists, who are seeing promising areas of the ancient lakebed to explore.

And finally, most of us know all too well how audio feedback works, and all the occasions to avoid it. But what about video feedback? What happens when you point a camera that a screen displaying the image from the camera? Fractals are what happens, or at least something that looks a lot like fractals. Code Parade has been playing with what he calls “analog fractals”, which are generated just by video feedback and not by computational means. While he’d prefer to do this old school with analog video equipment, it easy enough to replicate on a computer; he even has a web page that lets you arrange a series of virtual monitors on your screen. Point a webcam at the screen, and you’re off on a fractal journey that constantly changes and shifts. Give it a try.

Apollo DSKY Replica Looks The Part

It’s hard to say what exactly it is about the Apollo DSKY that captures so many hackers’ imaginations. Whatever it is, the “Display and Keyboard” unit from the Apollo Guidance Computer has inspired dozens of teardowns, simulations, and reproductions over the years, to varying degrees of success. But this mechanically faithful DSKY replica really knocks it out of the park in terms of attention to detail.

The product of [M. daSilva], this DSKY replica takes a somewhat different path than many of the others we’ve seen. By working from as many original documents as possible, he was able to reproduce the physical size and shape of the DSKY very accurately — no mean feat when working from copies of copies of the original paper prints. Still, the details that are captured, like the gussets and reinforcements that were added to strengthen the original die-cast parts, really make this DSKY look the part. It’s functional, too, thanks to a Raspberry Pi running VirtualAGC, with a Nextion 4.3″ LCD display standing in for the original electroluminescent display. We were surprised to learn the DSKY had a port for nitrogen purging the case; check out the video tour below for that and other tidbits.

Of course, just because [M. daSilva] chose to concentrate on dimensional accuracy for this go-around doesn’t preclude more faithful electronics in the future. Perhaps he can team up with [Ben Krasnow] or [Fran Blanche] and really make this a showpiece.

Continue reading “Apollo DSKY Replica Looks The Part”

Deploy Workaround Code To The Field When “The Field” Is Lunar Orbit

The Apollo missions still inspire people today, decades after they took place. A fortunate side effect of the global public relations campaign is that a lot of information is publicly available for us to review and process. We’re right around the 49th anniversary of Apollo 14 mission, so it was a good time for [Frank O’Brien] to take readers through Apollo Guidance Computer and the hack that saved Apollo 14 (while it was in lunar orbit).

Space fans would already know many parts of this piece, but [Frank] weaves it together into a single narrative around a problematic “Abort” button that was found to be making intermittent contact as the crew were preparing to land on the moon. An inconvenient timing would have unnecessarily aborted the mission, which was obviously Not Good. [Frank] brings us up to speed on AGC fundamentals, just enough to understand the technical constraints for the hack, devised within the time constraints they faced.

For those that prefer a short video summary [Scott Manley] covered this same hack on YouTube. And for another perspective on the scope of this task, remember this was years before we had vi or emacs. When they were contemplating flipping status bits as programs were running, it’s not trivial to do a global search for code that might examine those bits. Look at the tome of source code AGC programmer [Don Eyles] worked with. Space fans who want to learn more can check out [Don]’s book.

For the ultimate AGC talk, check out The Ultimate AGC Talk.

Maybe someday trips to the moon will be a commonplace thing, but Apollo will always be the pioneer.

Apollo Guidance Computer Saved From The Scrap Yard

NASA needed a small and lightweight computer to send humans on their journey to the Moon and back, but computers of the day were made out of discrete components that were heavy, large, complicated, and unreliable. None of which are good qualities for spaceflight. The agency’s decision to ultimately trust the success of the Apollo program on the newly developed integrated circuit was an important milestone in computer history.

Given the enormity of the task at hand and the monumental effort it took, it’s surprising to learn that there aren’t very many left in existence. But perhaps not as surprising as the fact that somebody apparently threw one of them in the trash. A former NASA contractor happened to notice one of these historic Apollo Guidance Computers (AGC) at an electronics recycling facility, and thankfully was able to save it from getting scrapped.

The AGC was actually discovered in 1976, but it was decided to get the computer working again in time for the recent 50th anniversary of the Moon landing. A group of computer scientists in California were able to not only get the computer up and running, but integrate it into a realistic simulator that gives players an authentic look at what it took to land on the Moon in 1969.

Restoring a computer of this age and rarity is no easy feat. There aren’t exactly spare parts floating around for it, and the team had to go to great effort to repair some faults on the device. Since we covered the beginning stages of the restoration last year, the entire process has been extensively documented in a series of videos on YouTube. So while it’s unlikely you’ll find an AGC in your local recycling center, at least you’ll know what to do with it if you do.

Continue reading “Apollo Guidance Computer Saved From The Scrap Yard”

Hackaday Links Column Banner

Hackaday Links: July 28, 2019

It looks like Apple is interested in buying Intel’s modem chip business. Seriously interested; a deal worth $1 billion could be announced as early as this week. That might look like a small potato purchase to the world’s biggest company – at least by market capitalization – but since the technology it will be buying includes smartphone modems, it provides a look into Apple’s thinking about the near future with regard to 5G.

It turns out that Make Magazine isn’t quite dead yet. [Dale Dougherty], former CEO of Maker Media, which went under in June, has just announced that he and others have acquired the company’s assets and reformed under the name “Maker Community LLC.” Make: Magazine is set to resume publication, going back to its roots as a quarterly publication in the smaller journal format; sadly there’s no specific word about the fate of Maker Faire yet.

The hoopla over the 50th anniversary of Apollo 11 may be over, but we’d be remiss not to call out one truly epic hack related to the celebration: the full restoration of an actual Apollo Guidance Computer. The AGC was from a test model of the Lunar Module, and it ended up in the hands of a private collector. Since November of 2018 the AGC has been undergoing restoration and tests by [Ken Shirriff], [Mike Stewart], and [Carl Claunch]. The whole effort is documented in a playlist by [Marc “CuriousMarc” Verdiell] that’s worth watching to see what was needed to restore the AGC to working condition.

With the summer sun beating down on the northern hemisphere, and air conditioners at working extra hard to keep things comfortable. [How To Lou] has a quick tip to improve AC efficiency. Turns out that just spraying a fine mist of water on the condenser coils works wonders; [Lou] measured a 12% improvement in cooling. It may not be the best use of water, and it may not work as well in very humid climates, but it’s a good tip to keep in mind.

Be careful with this one; between the bent spoon, the syringe full of amber liquid, and the little candle to heat things up, this field-expedient reflow soldering setup might just get you in trouble with the local narcotics enforcement authorities. Even so, knowing that you can assemble a small SMD board without a reflow oven might prove useful someday, under admittedly bizarre circumstances.

From the “Considerably more than 8-bits music” file, check out the Hull Philharmonic Orchestra’s “8-Bit Symphony.” If your personal PC gaming history included a Commodore 64, chances are you’ll recognize songs from titles like “Monty on the Run”, “Firelord”, “Green Beret”, and “Forbidden Forest.” Sure, composers like [Ben Daglish] and [Paul Norman] worked wonders with the three-channel SID chip, but hearing those tunes rendered by a full orchestra is something else entirely. We found it to be particularly good background music to write by.

Space Age Bitcoin Mining On An Apollo AGC

Imagine you’ve got an Apollo Guidance Computer, the machine that took men to the Moon 50 years ago. You’ve spent ages restoring it, and now it’s the only working AGC on the planet. It’s not as though you’re going to fly to the Moon with it, so what do you do with it? Easy – turn it into a perfectly awful Bitcoin mining rig.

The AGC that [Ken Shirriff] and others have been restoring barely resembles a modern computer. The AGC could only do about 40,000 operations per second, but raw speed was far less important than overall reliability and the abundant IO needed to run a crewed spacecraft. It was a spectacular success on the Apollo missions, but [Ken] wanted to know if turning it into a Bitcoin mining rig was possible.

[Ken] gives a great overview of how Bitcoin mining works, with one of the best explanations of the hashing algorithm we’ve seen. Getting that to run on the AGC was no mean feat, especially with limits imposed by the memory addressing scheme and the lack of machine instructions for manipulating words. He eventually got it working, though, clocking in at a screaming 10.3 seconds per Bitcoin hash. [Ken] estimates that the first coin will be successfully mined in a mere 400 zettaseconds, which is about a billion times older than the universe. With about 13 quadrillion years to the first ka-ching, you have plenty of time to watch a block mined in the video below; alas, it was an old block, so no coins were awarded to compensate the team for their efforts.

This isn’t the first time [Ken] has implemented a useless Bitcoin mine. The Xerox Alto mine was actually fast compared to the AGC, but it sure beats the IBM mainframe and punchcards.

Continue reading “Space Age Bitcoin Mining On An Apollo AGC”