All The Stars, All The Time

June 27, 2025 by Bryan Cockfield 5 Comments

Some of the largest objects in the night sky to view through a telescope are galaxies and supernova remnants, often many times larger in size than the moon but generally much less bright. Even so, they take up a mere fraction of the night sky, with even the largest planets in our solar system only taking up a few arcseconds and stars appearing as point sources. There are more things to look at in the sky than there are telescopes, regardless of size, so it might almost seem like an impossible task to see everything. Yet that’s what this new telescope in Chile aims to do.

The Vera C. Rubin Observatory plans to image the entire sky every few nights over a period lasting for ten years. This will allow astronomers to see the many ways the cosmos change with more data than has ever been available to them. The field of view of the telescope is about 3.5 degrees in diameter, so it needs to move often and quickly in order to take these images. At first glance the telescope looks like any other large, visible light telescope on the tops of the Andes, Mauna Kea, or the Canary Islands. But it has a huge motor to move it, as well as a large sensor which generates a 3200-megapixel image every 30 seconds.

In many ways the observatory’s telescope an imaging technology is only the first part of the project. A number of machine learning algorithms and other software solutions have been created to help astronomers sift through the huge amount of data the telescope is generating and find new irregularities in the data, from asteroids to supernovae. First light for the telescope was this month, June 2025, and some of the first images can be seen here. There have been a number of interesting astronomical observations underway lately even excluding the JWST. Take a look at this solar telescope which uses a new algorithm to take much higher resolution images than ever before.

Linear Solar Chargers For Lithium Capacitors

June 26, 2025 by Bryan Cockfield 24 Comments

For as versatile and inexpensive as switch-mode power supplies are at all kinds of different tasks, they’re not always the ideal choice for every DC-DC circuit. Although they can do almost any job in this arena, they tend to have high parts counts, higher complexity, and higher cost than some alternatives. [Jasper] set out to test some alternative linear chargers called low dropout regulators (LDOs) for small-scale charging of lithium ion capacitors against those more traditional switch-mode options.

The application here is specifically very small solar cells in outdoor applications, which are charging lithium ion capacitors instead of batteries. These capacitors have a number of benefits over batteries including a higher number of discharge-recharge cycles and a greater tolerance of temperature extremes, so they can be better off in outdoor installations like these. [Jasper]’s findings with using these generally hold that it’s a better value to install a slightly larger solar cell and use the LDO regulator rather than using a smaller cell and a more expensive switch-mode regulator. The key, though, is to size the LDO so that the voltage of the input is very close to the voltage of the output, which will minimize losses.

With unlimited time or money, good design can become less of an issue. In this case, however, saving a few percentage points in efficiency may not be worth the added cost and complexity of a slightly more efficient circuit, especially if the application will be scaled up for mass production. If switched mode really is required for some specific application, though, be sure to design one that’s not terribly noisy.

Static Electricity Remembers

June 25, 2025 by Bryan Cockfield 12 Comments

As humans we often think we have a pretty good handle on the basics of the way the world works, from an intuition about gravity good enough to let us walk around, play baseball, and land spacecraft on the moon, or an understanding of electricity good enough to build everything from indoor lighting to supercomputers. But zeroing in on any one phenomenon often shows a world full of mystery and surprise in an area we might think we would have fully understood by now. One such area is static electricity, and the way that it forms within certain materials shows that it can impart a kind of memory to them.

The video demonstrates a number of common ways of generating static electricity that most of us have experimented with in the past, whether on purpose or accidentally, from rubbing a balloon on one’s head and sticking it to the wall or accidentally shocking ourselves on a polyester blanket. It turns out that certain materials like these tend to charge themselves positively or negatively depending on what material they were rubbed against, but some researchers wondered what would happen if an object were rubbed against itself. It turns out that in this situation, small imperfections in the materials cause them to eventually self-order into a kind of hierarchy, and repeated charging of these otherwise identical objects only deepen this hierarchy over time essentially imparting a static electricity memory to them.

The effect of materials to gain or lose electrons in this way is known as the triboelectric effect, and there is an ordering of materials known as the triboelectric series that describes which materials are more likely to gain or lose electrons when brought into contact with other materials. The ability of some materials, like quartz in this experiment, to develop this memory is certainly an interesting consequence of an otherwise well-understood phenomenon, much like generating power for free from static electricity that’s always present within the atmosphere might surprise some as well.

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Pong In Discrete Components

June 24, 2025 by Bryan Cockfield 25 Comments

The choice between hardware and software for electronics projects is generally a straighforward one. For simple tasks we might build dedicated hardware circuits out of discrete components for reliability and low cost, but for more complex tasks it could be easier and cheaper to program a general purpose microcontroller than to build the equivalent circuit in hardware. Every now and then we’ll see a project that blurs the lines between these two choices like this Pong game built entirely out of discrete components.

The project begins with a somewhat low-quality image of the original Pong circuit found online, which [atkelar] used to model the circuit in KiCad. Because the image wasn’t the highest resolution some guesses needed to be made, but it was enough to eventually produce a PCB and bill of material. From there [atkelar] could start piecing the circuit together, starting with the clock and eventually working through all the other components of the game, troubleshooting as he went. There were of course a few bugs to work out, as with any hardware project of this complexity, but in the end the bugs in the first PCB were found and used to create a second PCB with the issues solved.

With a wood, and metal case rounding out the build to showcase the circuit, nothing is left but to plug this in to a monitor and start playing this recreation of the first mass-produced video game ever made. Pong is a fairly popular build since, at least compared to modern games, it’s simple enough to build completely in hardware. This version from a few years ago goes even beyond [atkelar]’s integrated circuit design and instead built a recreation out of transistors and diodes directly.

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Open A Portal To An NES Emulator

June 13, 2025 by Bryan Cockfield 2 Comments

The Portal games were revolutionary not only for their puzzle-based, narrative-driven gameplay, but also for their unique physics engine, which let players open portals anywhere and conserve momentum and direction through them. They’re widely regarded as some of the best video games ever made, but even beyond that they have some extra features that aren’t talked about as much. Namely, there are a number of level editors and mods that allow the in-game components to be used to build things like logic gates and computers, and this project goes even further by building a working NES emulator, all within Portal 2.

The main limitation here is that Portal 2 can only support a certain number of in-game objects without crashing, far lower than what would be needed to directly emulate NES hardware. The creator of the project, [PortalRunner], instead turned to Squirrel, the Portal 2 scripting language, and set about porting an existing NES emulator called smolnes to this scripting language. This is easier said than done, as everything in the code needs to be converted eight bits and then all of the pointers in smolnes need to be converted to use arrays, since Squirrel doesn’t support pointers at all. As can be easily imagined, this led to a number of bugs that needed to be sorted out before the game would run at all.

For those interested in code golfing, porting, or cross-compatibility, this project is a master class not only in the intricacies of the Portal 2 scripting language but in the way the NES behaves as well, not to mention the coding skill needed to recognize unique behaviors of the C language and the Squirrel scripting language. But eventually [PortalRunner] is able to get Super Mario Bros. running in Portal 2, albeit with low resolution and frame rate. Since we heard you like games within games, someone else put DOOM inside DOOM so you can DOOM while you DOOM.

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Learning The Basics Of Astrophotography Editing

June 12, 2025 by Bryan Cockfield 13 Comments

Astrophotography isn’t easy. Even with good equipment, simply snapping a picture of the night sky won’t produce anything particularly impressive. You’ll likely just get a black void with a few pinpricks of light for your troubles. It takes some editing magic to create stunning images of the cosmos, and luckily [Karl Perera] has a guide to help get you started.

The guide demonstrates a number of editing techniques specifically geared to bring the extremely dim lights of the stars into view, using Photoshop and additionally a free software tool called Siril specifically designed for astrophotograpy needs. The first step on an image is to “stretch” it, essentially expanding the histogram by increasing the image’s contrast. A second technique called curve adjustment performs a similar procedure for smaller parts of the image. A number of other processes are performed as well, which reduce noise, sharpen details, and make sure the image is polished.

While the guide does show some features of non-free software like Photoshop, it’s not too hard to extrapolate these tasks into free software like Gimp. It’s an excellent primer for bringing out the best of your astrophotography skills once the pictures have been captured, though. And although astrophotography itself might have a reputation as being incredibly expensive just to capture those pictures in the first place, it can be much more accessible by using this Pi-based setup as a starting point.

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Network Infrastructure And Demon-Slaying: Virtualization Expands What A Desktop Can Do

June 11, 2025 by Bryan Cockfield 21 Comments

The original DOOM is famously portable — any computer made within at least the last two decades, including those in printers, heart monitors, passenger vehicles, and routers is almost guaranteed to have a port of the iconic 1993 shooter. The more modern iterations in the series are a little trickier to port, though. Multi-core processors, discrete graphics cards, and gigabytes of memory are generally needed, and it’ll be a long time before something like an off-the-shelf router has all of these components.

But with a specialized distribution of Debian Linux called Proxmox and a healthy amount of configuration it’s possible to flip this idea on its head: getting a desktop computer capable of playing modern video games to take over the network infrastructure for a LAN instead, all with minimal impact to the overall desktop experience. In effect, it’s possible to have a router that can not only play DOOM but play 2020’s DOOM Eternal, likely with hardware most of us already have on hand.

The key that makes a setup like this work is virtualization. Although modern software makes it seem otherwise, not every piece of software needs an eight-core processor and 32 GB of memory. With that in mind, virtualization software splits modern multi-core processors into groups which can act as if they are independent computers. These virtual computers or virtual machines (VMs) can directly utilize not only groups or single processor cores independently, but reserved portions of memory as well as other hardware like peripherals and disk drives.

Proxmox itself is a version of Debian with a number of tools available that streamline this process, and it installs on PCs in essentially the same way as any other Linux distribution would. Once installed, tools like LXC for containerization, KVM for full-fledged virtual machines, and an intuitive web interface are easily accessed by the user to allow containers and VMs to be quickly set up, deployed, backed up, removed, and even sent to other Proxmox installations. Continue reading “Network Infrastructure And Demon-Slaying: Virtualization Expands What A Desktop Can Do” →