TechyMagThings

Over the years there have been many designs for pan-and-tilt camera mounts suitable for single board computer cameras. Often they mount small servos for the movement, but those in turn present problems when the device finds its way outdoors. [GOAT Industries] is here with a novel solution to this problem, instead of trying to cover up the servos on the mount itself, the whole thing is remotely controlled by linear actuators through Bowden cables.

Testing was performed using Mole-Grips instead of actuators, and revealed a few design quirks. There are hefty springs to provide tension, and since they work against 3D printed assemblies those in turn have to be reinforced. The layout of the Bowden cable run is also important, as it has a bearing on the amount of springinesss in the system. But it provides a versatile pan-and-tilt mount for a Pi camera mounted in an IP-rated box, which is the object of the exercise.

For anyone wishing to build one the files can be found in a GitHub repository, and there’s a video below showing the device in action. Meanwhile it’s by no means the first pan-and-tilt head we’ve seen here at Hackaday, however many others are by necessity much more substantial affairs.

Although easily dismissed by some as another cruel April Fools joke, Raspberry Pi’s announcement of a new 3 GB model of the Raspberry Pi 4 along with (more) price increases for other models was no joke. Courtesy of the ongoing RAMpocalypse, supplies of LPDDR4 and LPDDR5 are massively affected, leading to this new RPi 4 model with two 1.5 GB LPDDR4 chips, as these are apparently cheaper to source.

Affected in this latest price increase across RP’s product range are RPi 4 and 5 models with 4 or more GB of RAM, with price bumps ranging from $25 on the low end to $150 for the Raspberry Pi 500+. If you wanted a Raspberry Pi 5 with 16 GB of RAM, you’re now paying $300 for the privilege.

Obviously, this news has got people like [Jeff Geerling] rather down in the dumps, essentially stating that using SBCs like the RPi is now beyond the means of many hobbyists. While you can still use SBCs that use e.g. LPDDR2 RAM, such as the older RPi Zero, 2 and 3 models, [Jeff] himself is now moving more towards wrangling with snakes on MCUs, as these boards are so far not significantly affected in terms of price.

With current projections in the RAM market being that this year will still see more price increases, it remains hard to tell exactly how ‘temporary’ this situation will be. That said, using readily available, powerful and cheap MCUs like the ESP32 variants for projects isn’t a bad idea if you really don’t need to be running more than perhaps FreeRTOS.

If you’ve never heard of the threadless ball screw, which was invented over sixty years ago, [Angus] of Maker’s Muse has a video demonstrating the whole thing, covering its history and showcasing both its strengths and weaknesses. If you like seeing mechanical assemblies in action, give it a watch.

The device — consisting of little more than a smooth rod and three angled ball bearings — is a way to turn rotational motion into linear motion. Not a single belt, thread, or complex mechanical assembly in sight. While a simple nut on a threaded rod can turn rotation into linear motion, those come with their own issues. The threadless ball screw was one effort at finding a better way.

Threadless ball screws never really took off, although they were given some consideration for use in 3D printers back in the RepRap days. Today one can purchase quality CNC components without leaving one’s web browser, but back in the early 2000s things like lead screws and ball screws were rather more specialized, less accessible, and more expensive than they are today. RepRap folks had to make their own solutions. But while the threadless ball screw is a very DIY-friendly design, it was ultimately lacking in performance.

The main problem is they’re just not precise enough for anything like CNC work. [Angus] does some back-and-forth tests with a 3D printed unit that shows serious drift after only a few minutes. Now, he knows perfectly well that his 3D-printed test unit is far from ideal, but the rapidity at which it drifted was still a surprise. Making a carriage with two threadless ball screws — one at each end — performed a lot better, but was ultimately still flawed.

It’s not all bad. There’s zero backlash. They are mechanically simple, remarkably smooth, and utterly quiet. Also, [Angus] discovered that the maximum force this setup can be made to apply is surprisingly significant, and is directly related to the tension on the bearings. That means one can trivially adjust how easily the carriage slips  (or doesn’t) just by tightening or loosening the screw holding each bearing.

Sure, they’re not precise. But maybe you don’t need precision. Maybe you just need to move something back and forth in a strong & silent sort of way that can still slip gracefully (and quietly) if something goes awry, like bottoming out an axis. 3D printing makes it pretty easy to whip one up, so maybe there’s still a place for the threadless ball screw.

Although Windows 95 stole the show, Windows 3.0 was arguably the first version of Windows that more or less nailed the basic Windows UI concept, with the major 3.1 update being quite recognizable to a modern-day audience. Even better is that you can still install Win3.1 on a modern x86-compatible PC and get some massive improvements along the way, as [Omores] demonstrates in a recent video.

The only real gotcha here is that the AMD AM5 system with Asus Prime X670-P mainboard is one of those boards whose UEFI BIOS still has the ‘classic BIOS’ Compatibility Support Module (CSM) option. With that enabled, Win 3.1 installs without further fuss via a USB floppy drive from a stack of ‘backup’ floppies that someone made in the early 90s. [Omores] also tried it with CSMWrap, but with this USB to PS/2 emulation didn’t work.

Windows 3.1 supports ‘enhanced mode’ by default, which adds virtual memory and multi-tasking if you have an 80386 CPU or better. To fix crashing on boot and having to use ‘standard mode’ instead, the ahcifix.386 fix for the responsible SATA issue by [PluMGMK] should help, or a separate SATA expansion card.

For the video driver the vbesvga.drv by [PluMGMK] was used, to support all VESA BIOS Extensions modes. This driver has improved massively since we last covered it and works great with an RTX 5060 Ti GPU. There’s now even DCI support to enable direct GPU VRAM access for e.g. video playback, with audio also working great with only a few driver-related gotchas.

You know what they say — you can’t keep a good website down. OldVersion.com, the repository of outdated software that has been serving up old versions of tools you need for the last twenty-five years, is not going away as we reported last year. Not only is it sticking around, it’s gotten a retro facelift inspired by Windows 3.1 or OS/2. Mostly Windows, given the screensaver, but we’ll let you find that for yourself.

We’re thrilled to see that OldVersion has gotten the support they need to keep going after running into financial troubles. According to founder Alex Levine, some of that support came as a result of the Hackaday article reporting on the then-upcoming closure, so kudos to you guys for stepping up.

While we absolutely love the retro redesign of the new website, that’s one thing notably lacking — an obvious donation button. Well, that and old-school HTTP support so you can get on with your retromachines, but that, at least, is in the works according to the site roadmap. It’s a little weird that in this year of the common era 2026 you have to do extra work to give up on HTTPS functionality, but it is the way it is.

In the meantime, the site is fully usable as long as you have HTTPS capability, or go through a proxy. Perhaps you could use this ESP8266 code to get started making one, if you don’t want to embarrass your old computer by using something more powerful than it as a pass-through.

Speaking of proxies, if old versions of software aren’t enough for you, how about an old version of the internet? We heard you like old versions, so you can visit an old version of OldVersion!

Note that if you’re reading this after 01/04/2026, the look-and-feel of OldVersion.com may not match what’s depicted here.

Batteries are notoriously difficult pieces of technology to deal with reliably. They often need specific temperatures, charge rates, can’t tolerate physical shocks or damage, and can fail catastrophically if all of their finicky needs aren’t met. And, adding insult to injury, for many chemistries, the voltage does not correlate to state of charge in meaningful ways. Battery testers take many efforts to mitigate these challenges, but often miss the mark for those who need high fidelity in their measurements. For that reason, [LiamTronix] built their own.

The main problem with the cheaper battery testers, at least for [LiamTronix]’s use cases, is that he has plenty of batteries that are too large to practically test on the low-current devices, or which have internal battery management systems (BMS) which can’t connect to these testers. The first circuit he built to help solve these issues is based on a shunt resistor, which lets a smaller IC chip monitor a much larger current by looking at voltage drop across a resistor with a small resistance value. The Pi uses a Python script which monitors the current draw over the course of the test and outputs the result on a handy graph.

This circuit worked well enough for smaller batteries, but for his larger batteries like the 72V one he built for his electric tractor, these methods could draw far too much power to be safe. So from there he built a much more robust circuit which uses four MOSFETs as part of four constant current sources to sink and measure the current from the battery. A Pi Zero monitors the voltage and current from the battery, and also turns on some fans pointed at the MOSFETs’ heat sink to keep them from overheating. The system can be configured to work for different batteries and different current draw rates, making it much more capable than anything off the shelf.

We’ve seen our fair share of audiophile tomfoolery here at Hackaday, and we’ve even poked fun at a few of them over the years. Perhaps one of the most outrageously over the top that we’ve so far seen comes from [Pierogi Engineering] who, we’ll grant you not in a spirit of audiophile expectation, has made a set of speaker interconnects using liquid mercury.

In terms of construction they’re transparent tubes filled with mercury and capped off with 4 mm plugs as you might expect. We hear them compared with copper cables and from where we’re sitting we can’t tell any difference, but as we’ve said in the past, the only metrics that matter in this field come from an audio analyzer.

But that’s not what we take away from the video below the break. Being honest for a minute, there was a discussion among Hackaday editors as to whether or not we should feature this story. He’s handling significant quantities of mercury, and it’s probably not over reacting to express concerns about his procedures. We wouldn’t handle mercury like that, and we’d suggest that unless you want to turn your home into a Superfund site, you shouldn’t either. But now someone has, so at lease there’s no need for anyone else to answer the question as to whether mercury makes a good interconnect.