No Acid: Open ICs With A Tesla Coil

July 12, 2023 by 21 Comments

We’ve taken ICs apart before, but if they are in an epoxy package, it requires some lab gear and a lot of safety. Typically, you’ll heat the part and use fuming nitric acid (nasty stuff) in a cavity milled into the part to remove the epoxy over the die. While [100dollarhacker] doesn’t provide much detail, he appears to have used a Tesla coil to do it — no hot acid required.

Initial results were promising but took a long time to work. In addition, the coil gets very hot, and there is a chance of flames. The next attempt used a 3D printed cone with a fan to push the plasma over the chip. The first attempt shorted something out, and so far, each attempt eventually burns out the MOSFET driver.

We are always interested in the practical uses of Tesla coils and what’s inside ICs, so this project naturally appealed to us. We hope to see more success reported on the Hackaday.io page soon. Meanwhile, if you have a coil and an old IC lying around, try it. Maybe you’ll figure out how to make it work well and if you do, let us know.

The easiest chips to open are ceramic packages with a gold lid. Just use a hobby knife. There are less noxious chemicals you can use. If you want to use fuming nitric, be sure you know what you are doing and maybe make some yourself.

Discussing The Tastier Side Of Desktop 3D Printing

July 12, 2023 by 20 Comments

Not long after the first desktop 3D printers were created, folks started wondering what other materials they could extrude. After all, plastic is only good for so much, and there’s plenty of other interesting types of goop that lend themselves to systematic squirting. Clay, cement, wax, solder, even biological material. The possibilities are vast, and even today, we’re still exploring new ways to utilize additive manufacturing.

Ellie Weinstein

But while most of the research has centered on the practical, there’s also been interest in the tastier applications of 3D printing. Being able to print edible materials offers some fascinating culinary possibilities, from producing realistic marbling in artificial steaks to creating dodecahedron candies with bespoke fillings. Unfortunately for us, the few food-safe printers that have actually hit the market haven’t exactly been intended for the DIY crowd.

That is, until now. After nearly a decade in development, Ellie Weinstein’s Cocoa Press chocolate 3D printer kit is expected to start shipping before the end of the year. Derived from the Voron 0.1 design, the kit is meant to help those with existing 3D printing experience expand their repertoire beyond plastics and into something a bit sweeter.

So who better to host our recent 3D Printing Food Hack Chat? Ellie took the time to answer questions not just about the Cocoa Press itself, but the wider world of printing edible materials. While primarily designed for printing chocolate, with some tweaks, the hardware is capable of extruding other substances such as icing or peanut butter. It’s just a matter of getting the printers in the hands of hackers and makers, and seeing what they’ve got an appetite for.

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CP/M Porting In A Few Hours

July 12, 2023 by 13 Comments

If you’ve ever wanted to watch someone bring CP/M up on a new system and you have a couple of hours to spare, check out the recorded live stream of [Poking Technology]. The system in question is an Agon Light, a modern board with a Z-80-derived CPU. If you want to get right to the porting part, you might want to skip about 31 minutes of the nearly 2.5-hour video.

The first half hour is more about the built-in assembler and the board in general. If you’ve ever ported CP/M before, you know it isn’t as hard as bootstrapping a modern operating system. There are two major things you need: A BIOS, which is specific to your machine, and a BDOS, which is usually taken verbatim from the operating system sources. Your programs typically call one of the 40 or so functions in the BDOS.

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You’ve Got Mail: Sorting And The USPS

July 12, 2023 by 52 Comments

Snail mail. You may not think much of it these days, but the mail doesn’t stop and it never has. Every type of mail from postcards and letters to large envelopes and packages of all sizes moves every single day all over the US, even though it isn’t typically delivered on Sundays. Dealing with the ever-increasing volume of physical mail has called for the invention and evolution of automatic mail sorting machines that are used by both postal facilities and businesses alike.

While mail sorting machines have grown and matured over the years, the human element of the task remains intact. As long as people type addresses, write them by hand, and/or print them in handwriting fonts by the hundreds, there will need to be humans on hand to verify at least a few of them that are really hard to read.

There are roughly a dozen different types of mail sorting machines in 2023. In this series, we’re going to take a look at most of them, along with many other aspects of the United States Postal Service and its history.

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SuSE Take On Red Hat, Forking RHEL

July 12, 2023 by 18 Comments

One of the Linux stories of the moment has come from Red Hat, with their ongoing efforts to make accessing the source of their Red Hat Enterprise Linux product a paid-for only process. This has caused consternation and annoyance alike, from the open source community angry at any liberties taken with the GPL, and from the community of RHEL users and customers concerned as to what it might mean for them.

Now a new player has entered the fray in the form of SuSe, who have announced the creation of an RHEL fork with the intention of maintaining a freely-available Red Hat compatible operating system distribution.

This is good news for all who use Red Hat derived software and we expect the likes of Rocky Linux will be taking a close look at it, but it’s also a canny move from the European company as they no doubt hope to tempt away some of those commercial Red Hat customers with a promise of stability and their existing experience supporting Red Hat users through their mixed Linux support packages. We hope they’ll continue to maintain their relationship with the open source world, and that the prospect of their actions unleashing a new commercial challenge causes Red Hat to move away from the brink a little.

Need some of the backstory? We’ve got you covered.

The perfect header for this story comes via atzerok, CC BY-SA 2.0.

Proper Decoupling Capacitors

July 12, 2023 by 37 Comments

If you’ve been building circuits for any length of time, you probably know you need decoupling capacitors to keep your circuits stable. But even though it’s a favorite technique of ours, just scattering some around your PCB and hoping for the best isn’t necessarily the best approach. If you want to dig deeper into the why and how of decoupling, check out [Stephen Fleeman’s] post on the topic.

It is easy to think of capacitors as open circuits at DC and short circuits at high frequencies, shunting noise to ground. But the truth is more complex than that. Stray resistance and inductance mean that your simple decoupling capacitor will have a resonant frequency. This limits the high frequency protection so you often see multiple values used in parallel to respond to different frequencies.

Because the stray resistance and inductance plays a part, you may want to use fatter traces — less resistance — and shorter runs for less inductance. Of course, you can also use power and ground planes on the PCB as a form of decoupling. At the end of the post, [Stephen] talks a little about the importance of digital and analog ground that interact in a specific way.

If you want to do some empirical testing, you can build a test rig and do the work. Or check with [Bil Herd] about PCB inductance.

High School Student Builds Inexpensive Centrifuge

July 11, 2023 by 31 Comments

Having a chemistry lab fully stocked with all necessary equipment is the dream of students, teachers, and professors alike, but a lot of that equipment can be prohibitively expensive. Even in universities, labs are often left using old or worn-out equipment due to cost. So one could imagine that in high schools this is even a more pronounced problem. High school student [Aidan Miller] has solved this problem with at least one piece of lab equipment, bringing the cost for a centrifuge down to around $10 USD.

Part of the savings is due to the fact that [Aidan] has put together a smaller sized centrifuge, known as a micro-centrifuge. The function is still the same though, spinning samples to separate them out the constituents by weight. The 3D printed base of the centrifuge houses a switch and 9 V battery and also holds a small motor which spins the rotor. The rotor itself is also 3D printed, and needed to be a very specific shape to ensure that it could hold the samples properly at high RPM and maintain reasonable balance while spinning.

As a project it’s fairly simple and straightforward to build, but the more impressive thing here is how much it brings down the cost of lab equipment especially for high school labs that might otherwise struggle for funding. Of course it requires the use of a 3D printer but the costs of those have been coming down significantly as well, especially for things like this portable 3D printer which was also built by a high school student.

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