Year: 2025

Pluto’s Not A Planet, But It Is A Spectrum Analyzer

April 6, 2025 by 8 Comments

The RTL-SDR dongles get most of the love from people interested in software-defined radio, but the Pluto is also a great option, too. [FromConceptToCircuit] shares code to turn one of these radios into a spectrum analyzer that sweeps up to 6 GHz and down to 100 MHz. You can see a video of how it works below.

While it may seem that 100 MHz is a bit limiting, there’s plenty of activity in that range, including WiFi, Bluetooth, radio systems, both commercial and amateur, and even cell phones.

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Command And Conquer Ported To The Pi Pico 2

April 6, 2025 by 9 Comments

A couple of months back, Electronic Arts did something uncharacteristically benevolent and released several of the old Command and Conquer games under the GPLv3. Logically, we knew that opened the doors up to the games being ported to new operating systems and architectures, but we admit that it was still a little surprising to see Command and Conquer: Red Alert running on the Raspberry Pi Pico 2.

[Charlie Birks] documented the process of getting the 1996 game up and running on the microcontroller in a series of Mastodon posts spanning a few days in March. Seeing the incremental progress made each day makes for interesting reading, as he moves from the game just barely starting up to being able to complete missions and eventually even get multiplayer going between two Picos.

As [Charlie] clarifies, he’s technically using the Pimoroni Pico Plus 2 W, which takes the RP2350B from the official Pico 2, adds 8 MB of PSRAM, and bumps the onboard flash to 16 MB. The upgraded specs and an SD card are required to get the game running, as content that would have originally been held in RAM on the computer must instead be pulled from flash.

For an even more streamlined experience, he eventually slaps the Pico Plus 2 W into the Pimoroni Pico VGA Demo Base — which provided not only an integrated SD card slot, but (as the name implies) VGA output.

It’s still early days, but [Charlie] has been pushing all of his code changes into his fork of Red Alert on GitHub for anyone who wants to play along at home. If you get his fork compiled and running on your own Pico, we’d love to hear about it in the comments.

Reverse Engineering The IBM PC110, One PCB At A Time

April 6, 2025 by 10 Comments

There’s a dedicated group of users out there that aren’t ready to let their beloved IBM PC110 go to that Great Big Data Center in the Sky. Unfortunately, between the limited available technical information and rarity of replacement parts, repairing the diminutive palmtops can be tricky.

Which is why [Ahmad Byagowi] has started a project that aims to not only collect all the available schematics and datasheets that pertain to the machine, but to reverse engineer all of the computer’s original circuit boards. Working from optical and x-ray scans, the project has already recreated the motherboard, power supply, modem, keyboard, and RAM module PCBs in KiCad.

Just last week the project released production-ready Gerbers for all the boards, but considering there have been 45+ commits to the repository since then, we’re going to assume they weren’t quite finalized. Of course, with a project of this magnitude, you’d expect it to take a few revisions to get everything right. (Hell, we’ve managed to screw up board layouts that had fewer than a dozen components on them.)

If you’d like to lend a hand, [Ahmad] says he could use the help. Beyond checking the boards for problems and reporting issues, he’s also on the hunt for any datasheets or other documentation that can be found for the PC110 or its components. It looks like there’s still schematic work that needs to be done as well, so if your idea of zen is figuring out how ~30 year old computers were wired up internally, this might be the perfect summer project for you.

Interestingly, our very own [Arya Voronova] has been working on creating a drop-in replacement motherboard for the Sony Vaio P using KiCad and imported board images. That hobbyists are now able to do this kind of work using free and open source tools is a reminder of just how far things have come in the last few years.

Thanks to [adistuder] for the tip.

An Amstrad PCW Receives A Bit Of Love

April 6, 2025 by 6 Comments

If Clive Sinclair’s genius in consumer electronics was in using ingenious hacks to make cheaper parts do greater things, then his Amstrad competitor Alan Sugar’s was in selling decade-old technology to consumers as new and exciting. His PCW series of computers are a great example, 1970s CP/M machines smartly marketed for late 1980s home offices. They were a popular choice at the time, and [Retro Recipes] has one. In  a video filmed in period standard definition he’s taking us through a repair to its Gotek drive, and then a RAM upgrade.

The repair and upgrade are fairly straightforward, the former being a failed OLED screen on the drive and the latter being the installation of a bank of DIP memory chips. The interest lies in how they cost-minimised a CP/M machine as a consumer product. The board relies heavily on custom chips as you might expect, and there’s a brief glimpse of one of those unusual 3″ floppy drives. The power supply is part of the monitor board as was often the case with Amstrad machines, and the whole thing is about as simple as it can be. The full video can be found below the break.

We’re guessing that particularly in the UK there will be plenty of PCWs still languishing in dusty attics, but surprisingly given their popularity at the time we see less of them that might be expected. There has been a significantly upgraded model on these pages though.

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Emulating IPhone On QEMU

April 6, 2025 by 3 Comments

[Georges Gagnerot] has been trying to emulate iOS and run iPhone software in a virtual environment. There were a few choices, and qemu-t8030 had a number of interesting features that you can check out in his post.

The project requires a patched QEMU, and [Georges] did some basic jailbreaking techniques. The real problem, of course, was not having the Apple Silicon GPU. Older versions of iOS let you select software rendering, but that option is gone on newer versions. However, it was possible to patch the phone to still use software rendering. There are still apps that directly use Metal or OpenGL that won’t run, but that’s another problem.

There is a plan to explore forwarding GPU calls to a real device. However, that seems difficult so it will have to wait for now.

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Celebrating 30 Years Of Windows 95 At VCF

April 6, 2025 by 78 Comments

It’s been 30 years since Windows 95 launched. [Ms-Dos5] and [Commodore Z] are celebrating with an epic exhibit at Vintage Computer Festival East 2025. They had no fewer than nine computers — all period-correct machines running versions of Windows 95. The pictures don’t do it justice, so if you are near Wall, NJ, on Sunday, April 5, 2025, definitely go check out this and the rest of the exhibits at VCF.

An exhibit like this isn’t thrown together overnight.  [Commodore Z] and [Ms-Dos5] worked for months to assemble the right mix of desktops, laptops, and peripherals to showcase Windows 95. Many of the computers are networked as well – which was no easy task.

One particular Thinkpad 760e required pliers and force to remove a stuck PCMCIA modem card. After a struggle that was ultimately destructive to the card, the pair determined it was stuck due to a sticker that had effectively glued the card into the laptop. As the sticker finally gave up, the card popped itself out of the laptop.

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A Low F Number Lens, From Scratch

April 6, 2025 by 52 Comments

The F-number of a photographic lens is a measure of its light-gathering ability, and is expressed as its aperture diameter divided by its focal length. Lenses with low F-numbers are prized by photographers for their properties, but are usually expensive because making a good one can be something of a challenge. Nevertheless [Rulof] is giving it a go, making an 80mm F0.5 lens with a Sony E-mount. The video below the break has all the details, and also serves as a fascinating primer on lens design if you are interested.

Rather than taking individual lenses, he’s starting with the second-hand lens from an old projector. It’s got the required huge aperture, but it’s by no means a photographic lens. An interesting component is his choice of diaphragm for the variable aperture, it’s a drafting aid for drawing circles which closely resembles a photographic part. This is coupled with the triplet from an old SLR lens in a 3D-printed enclosure, and the result is a lens that works even if it may not be the best. We know from experiences playing with lens systems that adjusting the various components of a compound lens like this one can be very difficult; we can see it has the much sought-after bokeh or blurred background, but it lacks sharpness.

Perhaps because a camera is an expensive purchase, we don’t see as much of this kind of hacking as we’d like. That’s not to say that lenses don’t sometimes make their way here.

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