High School Student Builds Inexpensive Centrifuge

July 11, 2023 by Bryan Cockfield 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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Phone Thermal Cameras Get Open Source Desktop Tools

July 11, 2023 by Tom Nardi 14 Comments

Whenever phone-based thermal cameras are brought up here on Hackaday, we inevitably receive some comments about how they’re a bad investment compared to a standalone unit. Sure they might be cheaper, but what happens in a couple years when the app stops working and the manufacturer no longer feels like keeping it updated?

It’s a valid concern, and if we’re honest, we don’t like the idea of relying on some shady proprietary app just to use the camera in the first place. Which is why we’re so excited to see open source software being developed that allows you to use these (relatively) inexpensive cameras on your computer. [Les Wright] recently sent word that he’s been working on a project called PyThermalCamera which specifically targets the TOPDON TC001, which in turn is based on a project called P2Pro-Viewer developed by LeoDJ for the InfiRay P2 Pro.

Readers may recall we posted a review of the P2 Pro last month, and while the compact hardware was very impressive, the official Android software lacked a certain degree of polish. While these projects won’t help you on the mobile front in their current form, it’s good to know there’s at least a viable “Plan B” if you’re unwilling or unable to use the software provided from the manufacturer. Naturally this also opens up a lot of new possibilities for the camera, as being connected to a proper Linux box means you can do all sorts of interesting things with the video feed.

The two video feeds on the left are combined to produce the final thermal image.

Speaking of the video feed, we should say that both of these projects were born out of a reverse engineering effort by members of the EEVblog forums. They figured out early on that the InfiRay (and other similar models) were picked up as a standard USB video device by Linux, and that they provided two video streams: one being a B&W feed from the camera where the relative temperature is used as luminance, and the other containing the raw thermal data cleverly encoded into a green-tinted video. With a little poking they found an FFmpeg one liner that would combine the two streams, which provided the basis for much of the future work.

In the video below, you can see the review [Les] produced for the TOPDON TC001, which includes a demonstration of both the official Windows software and his homebrew alternative running on the Raspberry Pi. Here’s hoping these projects inspire others to join in the effort to produce flexible open source tools that not only unlock the impressive capabilities of these new thermal cameras but save us from having to install yet another smartphone application just to use a device we purchased.

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Tearing Down And Improving A Professional Power Supply

July 11, 2023 by Al Williams 11 Comments

[OZ2CPU] has an HP power supply that is about 30 years old. It looks brand new, though, and has three outputs and includes tracking for the adjustable positive and negative supply. After a quick demo of the unit’s features, he tears it all down so we can see inside. You can catch the video below.

Some similar supplies offer a 10-turn adjustment knob, but this one doesn’t. Inside is a beefy transformer and quite a few through-hole components. There was room to change the main adjusted pot to a 10-turn unit, so he made the mod.

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An Open-Source Antikythera Mechanism

July 11, 2023 by Bryan Cockfield 19 Comments

When the Antikythera Mechanism was first discovered, it wasn’t viewed as the wonder that we know it today. Originally the divers who found the device and the first scientists to look at it wrote it off as an astrolabe or other some other common type of clock. It wasn’t until decades later when another set of scientists x-rayed the device and surveyed more of the shipwreck where it was found that it began to become one of the more important archaeological discoveries in history. There have been plenty of attempts to recreate this device, and this replica recreates the mechanisms of the original but is altered so it can be built in a modern workshop.

The build, which took the creators several years of research and development to complete, started off with the known gear schemes found on the original device. However, the group wanted to make it with modern technology including 3D printers and laser cutters, so although they worked from an understanding of the original 2000-year-old device there are some upgrades and changes to accommodate those who want to build this in a modern workshop. Gears made from plastic instead of brass have more friction, which needed to be reduced by building custom bearings machined out of brass. And to complete the machine a number of enclosures of various styles are available to use as well.

Additionally, all of the designs and schematics for this build are open source for anyone to build or modify as they would like, although the group putting this together does plan to sell various parts for this as well. There will be some issues with use, as they point out, since the ancient Greeks didn’t have a full enough understanding of cosmology to get a machine like this to stay accurate for two thousand years, but it’s a fascinating build nonetheless. Reasearchers are still discovering new things about this device too, including the recent find of an earliest possible start date for the machine.

Linux Device Drivers In Only A Few Years

July 11, 2023 by Al Williams 10 Comments

[Johannes 4GNU_Linux] has been filming a video series on how to write Linux device drivers for a couple of years now, but luckily, you won’t need that long to watch them or to create your own driver. He’s added some recent videos to the series, like the one below, but might want to rewind a few years and start at the beginning.

If you build your own hardware for Linux, you’ll probably eventually want to write a driver which runs as a privileged program. While there are many things you can do in user space, for the ultimate control and performance, you can’t beat a driver.

One problem, though, is that drivers can really crash your system in a big way. In the old days, it was common to have a dedicated system for driver development. Today, for many drivers, you can get away with running a virtual machine that you can crash and reload without much trouble.

The videos cover diverse topics like interrupts, completions, polling, and threads. He even uses a Raspberry Pi, which will be very useful for many embedded projects. Of course, the trend these days is to have one driver — like the USB driver — and have it provide user-space access so that everyone doesn’t have to write their own drivers. But, as usual, that only goes so far.

We aren’t sure how many more videos there will be, but if you make it through the first 31, maybe more will be waiting for you. It has been a while since we looked at SPI drivers in Linux. As an example of why you might want to roll your own, consider a custom FPGA driver.

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Retrotechtacular: Better Living Through A-Bombs

July 11, 2023 by Al Williams 42 Comments

Usually, if you are listening to people debate about nuclear issues, it is one of two topics: how to deal with nuclear weapon stockpiles or if we want nuclear power plants in our backyard. But there was a time when the US and the USSR had more peaceful plans for nuclear bombs. While peaceful plans for nuclear bombs might sound like an oxymoron, there was somewhat of a craze for all things nuclear at some point, and it wasn’t clear that nuclear power and explosives wouldn’t take over many industries as the transistor did, or the vacuum tube before it.

You may have heard about Project (or Operation) Plowshare, the US effort to find a peaceful use for all those atom bombs. The Atomic Energy Commission video below touts the benefits “for all nations.” What benefits? Mostly moving earth, including widening the Panama Canal or creating a new canal, cutting highways through mountains, assisting mining and natural gas production, and creating an artificial harbor. There was also talk of using atomic blasts to create new materials and, of course, furthering the study of the atom.

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Reverse-Engineering Helps Typesetting Machine Punch Paper Tape Again

July 11, 2023 by Dan Maloney 14 Comments

[Scott M. Baker] wants a paper tape punch for his retrocomputer collection. That’s fine with us, we don’t judge. In fact, these electromechanical peripherals from the past have a lot going for them, especially the noise. But alas, such things are a little hard to come by these days, and rolling one from scratch would be a difficult proposition indeed. What to do?

Luckily, we live in the future, and eBay holds all sorts of wonders, including these typesetter keyboards from the 1970s, which [Scott] promptly reverse-engineered. We’ll get to the details in a minute, but first, can we just take a moment to think about the workflow these things were part of? These aren’t terminals — they lack any kind of IO apart from the punched paper tape they spewed out. The operator’s job was to punch in copy without any kind of feedback that they were hitting the right keys, and just sent the paper tap record of the session off to the typesetting machines. And you think your job sucks.

To give this thing an interface, [Scott] first had to revive the power supply, whose capacitors had seen sunnier days. With that out of the way, he set about understanding the CPU-less machine by analyzing its 7400-series logic, as well as planning how to make the native 6-bit output into a more manageable 8-bit. Thankfully, the tape punch already had solenoids for the top two bits, but finding a way to drive them wasn’t trivial.

The solution was to bypass a buffer so that the bits for the desired character can be set with a Raspberry Pi and an ATF22V10 programmable logic device. That’s enough to force the punch to do its thing; actually getting it to talk to something else, perhaps even [Scott]’s Heathkit H-8 computer.

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