[Ken Shirriff] Becomes a Core Memory Repairman (Again)

Lately, [Ken Shirriff] has been on some of the most incredible hardware adventures. In his most recent undertaking we find [Ken] elbow-deep in the core memory of a 50-year-old machine, the IBM 1401. The computer wasn’t shut down before mains power was cut, and it has refused to boot ever since. The culprit is in the core memory support circuitry, and thanks to [Ken’s] wonderful storytelling we can travel along with him to repair an IBM 1401.

From a hardware standpoint core memory makes us giddy. It’s a grid of wires with ferrite toroids at every intersection. Bits can be …read more

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Hexbright Repair Keeps Torch Out of Landfill

The Hexbright was a Kickstarter project from a few years ago, to create an open source, rechargeable LED light. [Nick] quite likes them, and has learned a thing or two about keeping them operational.

The torches have a few key issues which [Nick] lists for us, before outlining the necessary repairs. These problems highlight certain design flaws, something one might expect for a hardware product from a new startup. Components inside are easily damaged if the device is dropped, and there is no reverse polarity protection on the battery.

It’s always disappointing to see a product in the marketplace fail …read more

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Modernizing Puerto Rico’s Grid

After two massive hurricanes impacted Puerto Rico three months ago, the island was left with extensive damage to its electrical infrastructure. Part of the problem was that the infrastructure was woefully inadequate to withstand a hurricane impact at all. It is possible to harden buildings and infrastructure against extreme weather, and a new plan to restore Puerto Rico’s power grid will address many of these changes that, frankly, should have been made long ago.

Among the upgrades to the power distribution system are improvements to SCADA systems. SCADA allows for remote monitoring and control of substations, switchgear, and other equipment …read more

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3D Printed Gear Serves Seven Months Hard Labor

Even the staunchest 3D printing supporter would have to concede that in general, the greatest strength of 3D printing is not in the production of final parts, but in prototyping. Sure you can make functional prints, as the pages of this site will attest; but few would argue that you wouldn’t be better off getting your design cut out of metal or injection molded if you planned on putting the part into service over the long term. Especially if the part was to be subjected to rough service in an industrial setting.

While that’s valid advice, it certainly isn’t the …read more

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Get Down to the Die Level with this Internal Chip Repair

Usually, repairing a device entails replacing a defective IC with a new one. But if you’ve got young eyes and haven’t had caffeine in a week, you can also repair a defective chip package rather than replace it.

There’s no description of the incident that resulted in the pins of the QFP chip being ablated, but it looks like a physical insult like a tool dropped on the pins. [rasminoj]’s repair consisted of carefully grinding away the epoxy cap to expose the internal traces leading away from the die and soldering a flexible cable with the same pitch between the …read more

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Fix Everything and Get Your Own Flailing Arms Tube Man

The staple of used car dealerships that prompted Houston to ban all ‘attention getting devices’ is called an ‘air dancer’ and was invented in 1996. And now you can build your own, even if until now the space requirements kept you from doing so.

[dina Amin] shows how to make one from a bunch of discarded hair dryers and stuff everybody is likely to find in his or her workshop. While the build as such is rather basic — these things are really simple devices after all — [dina Amin]’s project video takes us through the interesting detours that turn …read more

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