Day: July 19, 2022

Tech In Plain Sight: Fire Hydrants

July 19, 2022 by 42 Comments

You probably see them so often that you don’t even notice they are there. Fire hydrants are one of those things that aren’t interesting until you need them, but then they are of paramount importance. You sometimes hear them called fireplugs and it made us wonder what was a plug about it. Perhaps it was because that’s where you plug in your hose? Turns out, no. The real story is much stranger. Not to mention, did you know that there are even “dry” fire hydrants?

Apparently, in the 16th century, water mains were made of wood. When there was a fire, a team would dig the cobblestones out to expose the wooden mains and cut a hole to make an ad hoc well to fill buckets or to pump. Of course, after the fire, you had to repair the mains and that was done with a plug. The city would keep a record of plugs so that if a fire was nearby in the future, you could just “pull the plug” instead of making a new hole.

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The printer in question - it's tall, about a meter and a half tall, in fact!

Hackaday Prize 2022: $40k Stratasys Printer Fix Costs $1

July 19, 2022 by 36 Comments

Companies don’t treat equipment in the same way that we, hobbyists, do. When it comes to reassessing equipment state, there’s calculations to be done – how many failures it’s experienced, what’s the rate of the support contract for it (often increasing as equipment ages), and whether it’d be more price-efficient to just buy a new one. Hobbyists aren’t tied to commercial support contracts that prohibit DIY repair, however. We can investigate things and try our luck, and in many cases, the repair will be super simple and satisfying! Today’s lucky repair story is about [Gregor], who has acquired a written-off ±$40k Stratasys 3D printer for peanuts, and repaired it with $1 in parts.

The error code shown on the display indicated an extruder changer error — yes, this is a dual extruder printer! Earlier, [Gregor] noted that some of the chamber lighting LEDs failed, very likely because of the constant heat in the chamber. After investigating the infrared LED responsible for extruder change detection, it indeed had failed as well, presumably for the same reason. After the installation of a new SMD LED, the error message went away. Thus concludes the story of [Gregor] getting himself a new professional-grade printer! He also documents other possible failure modes, some just as easy to fix. In short, if you ever spot a Stratasys Dimension printer for sale, you might want to consider it!

As it turns out, this isn’t the only Stratasys success story we’ve seen on Hackaday.io. After you’ve repaired your newly obtained Stratasys, you might want to bypass the cartridge DRM, by the way. Got repairs of your own to share, industrial printer or otherwise? Submit it for the 2022 Hackaday Prize, there’s still a few days left in the Hack it Back round!

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Modular Z80 Really Racks Up The Retrocomputer Cred

July 19, 2022 by 24 Comments

Very few retrocomputing projects are anything other than a labor of love. There’s really no practical reason to build a computer that is woefully inadequate for just about any task compared to even an entry-level PC today. But the lack of a practical reason to do something rarely stops a hacker, as with this nifty modular Z80-based rack computer.

Actually, there’s at least one area where retrocomputers excel compared to their modern multi-core gigahertz counterparts — and that’s nostalgia. That’s what [Ricardo Kaltchuk] was going for with his build, which started by finding a Z80 and an Intel 8251 USART in his parts bin. Those formed the core of what would become the “Proton” computer, a modular beauty built around 7 cm by 10 cm PCBs that plug into a backplane inside a rack made from aluminum angle. Aside from the power supply and the Z80 CPU, other modules include a RAM card with a zero insertion force socket for an EPROM, a mass-storage module sporting a 128 MB Compact Flash card, plus modules for standard serial and I2C comms.

The fit and finish are excellent, and the performance is impressive. The Proton runs CP/M and boasts a ton of old applications that will bring back some memories, like SuperCalc and dBase. We’d venture a bet that WordStar is in there someplace, or easily could be. The video below is a little rough, but shows everything off really well.

In some ways, the Proton reminds us of the RC2014, but its fit and finish are what bring this build home. That’s not to take away from the work [Ricardo] obviously put into documentation, though. The 62-page manual has every detail of every module, plus instructions for building one of your own.

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