Author: Jenny List

3215 Articles

A GEM Of A Desktop Environment

September 18, 2025 by 25 Comments

Desktop environments are the norm as computer interfaces these days, but there was once a time when they were a futuristic novelty whose mere presence on a computer marked it out as something special. In the early 1980s you could buy an expensive but very fancy Mac from Apple, while on the PC there were early Windows versions, and GEM from Digital Research. It’s something of a footnote here in 2025, and some insight as to why comes from [Programming at the right level] with a retrospective on the software.

Coming from the perspective of an Atari user whose ST shipped with a version of GEM, it tracks the projects from its earliest roots with a Xerox employee, through development to launch on the PC and Atari ST. We learn about an Apple legal threat that resulted in the hobbled interface many of us remember from later GEM versions, and about the twists and turns in its path before the final dissolution of DR in the early 1990s.

From 2025 it’s clear that Windows won the PC desktop battle not by being special but by being the default; when GEM was an add-on extra it would have been a tough sell. The software was eventually made open-source by the eventual owner of the DR assets, Caldera (when they weren’t trying to torpedo Linux, presumably), and can be run today on FreeDOS.

GEM header image: Rolf Hartmann, CC BY-SA 3.0.

Give Your Band The Music Of The Bands

September 18, 2025 by 3 Comments

The way to get into radio, and thence electronics, in the middle years of the last century, was to fire up a shortwave receiver and tune across the bands. In the days when every country worth its salt had a shortwave station, Cold War adversaries boomed propaganda across the airwaves, and even radio amateurs used AM that could be listened to on a consumer radio, a session in front of the dial was sure to turn up a few surprises. It’s a lost world in the 21st century, as the Internet has provided an easier worldwide medium and switch-mode power supplies have created a blanket of noise. The sounds of shortwave are thus no longer well known to anyone but a few enthusiasts, but that hasn’t stopped [gnd buzz] investigating their potential in electronic music.

There’s very little on the air which couldn’t be used in some form by the musician, but the samples are best used as the base for further processing. One example takes a “buzzer” signal and turns it into a bass instrument. The page introduces the different types of things which can be found on the bands, for which with the prevalence of WebSDRs there has never been a lower barrier to entry.

If you’re too young to have scanned the bands, a capable receiver can now be had for surprisingly little.

Radio dial header: Maximilian Schönherr, CC BY-SA 3.0.

When Is Your Pyrex Not The Pyrex You Expect?

September 17, 2025 by 22 Comments

It’s not often that Hackaday brings you something from a cooking channel, but [I Want To Cook] has a fascinating look at Pyrex glassware that’s definitely worth watching. If you know anything about Pyrex it’s probably that it’s the glass you’ll see in laboratories and many pieces of cookware, and its special trick is that it can handle high temperatures. The video takes a look at this, and reveals that not all Pyrex is the same.

Pyrex was a Corning product from the early 20th century, and aside from its many laboratory and industrial applications has been the go-to brand for casserole dishes and much more in the kitchen ever since. It’s a borosilicate glass, which is what gives it the special properties, or at least in some cases it used to be a borosilicate glass. It seems that modern-day American Pyrex for the kitchen is instead a soda glass, which while it still makes a fine pie dish, doesn’t quite have the properties of the original.

The video explains some of the differences, as well as revealing that the American version is branded in lower case as pyrex while the European version is branded uppercase as PYREX and retains the borosilicate formulation. Frustratingly there’s no quick way to definitively tell whether a piece of lower-case pyrex is soda glass or not, because the brand switch happened before the formulation switch.

In all probability in the kitchen it makes little difference which version you own, because most users won’t give it the extreme thermal shock required to break the soda version. But some Hackaday readers do plenty of experiments pushing the limits of their glassware, so it’s as well to know that seeking out an older PYREX dish could be a good move.

If you’d like to know more about glass, we’ve got you covered.

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It’s A Variable Capacitor, But Not As We Know It

September 17, 2025 by 22 Comments

Radio experimenters often need a variable capacitor to tune their circuits, as the saying goes, for maximum smoke. In decades past these were readily available from almost any scrap radio, but the varicap diode and then the PLL have removed the need for them in consumer electronics. There have been various attempts at building variable capacitors, and here’s [radiofun232] with a novel approach.

A traditional tuning capacitor has a set of meshed semicircular plates that have more of their surface facing each other depending on how far their shaft is turned. The capacitor presented in the first video below has two plates joined by a hinge in a similar manner to the covers of a book. It’s made of tinplate, and the plates can be opened or closed by means of a screw.

The result is a capacitor with a range from 50 to 150 picofarads, and in the second video we can see it used with a simple transistor oscillator to make a variable frequency oscillator. This can form the basis of a simple direct conversion receiver.

We like this device, it’s simple and a bit rough and ready, but it’s a very effective. If you’d like to see another unusual take on a variable capacitor, take a look at this one using drinks cans.

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The Practicality Of Solar Powered Meshtastic

September 17, 2025 by 18 Comments

A Meshtastic node has been one of the toys of the moment over the last year, and since they are popular with radio amateurs there’s a chance you’ll already live within range of at least one. They can typically run from a lithium-ion or li-po battery, so it’s probable that like us you’ve toyed with the idea of running one from a solar panel. It’s something we have in common with [saveitforparts], whose experiments with a range of different solar panels form the subject of a recent video.

He has three different models: one based around a commercial solar charger, another using an off-the-shelf panel, and a final one using the panel from a solar garden light. As expected the garden light panel can’t keep an ESP32 with a radio going all day, but the other two manage even in the relatively northern climes of Alaska.

As a final stunt he puts one of the nodes out on a rocky piece of the southern Alaskan coastline, for any passing hacker to find. It’s fairly obviously in a remote place, but it seems passing cruise ships will be within its range. We just know someone will take up his challenge and find it.

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How To Have A Medium Format Camera Without Breaking The Bank

September 16, 2025 by 11 Comments

For most people, experimentation with film photography comes in the form of the 35 mm format. Its ubiquity in snapshot photography means cameras are readily available at all levels, and the film offers a decent compromise between resolution and number of shots per dollar spent.

For those who wish to take their film photography further there’s the so-called medium format 120 roll film, but here opting for a higher-end camera can become expensive. Fortunately [Javier Doroteo] is here with a 3D printed medium format camera designed to use lenses intended for the Mamiya Press cameras, and from where we’re sitting it looks very nicely designed indeed.

All the files can be found on Printables along with a list of the other parts required. It’s made simple by the Mamiya lenses incorporating the shutter, but there’s still a lot of attention that has been paid to the back of the camera. This is the third version of the design and it shows, details such as the film holder and light proofing are well thought out.

Photography is so often a world in which collecting the latest kit is seen as more important than the photographs themselves, so we like and encourage camera hackers as a reaction to all that. If you’d like to see another medium format camera, this certainly isn’t the first we’ve brought you.

This Rail Speeder Needs A Little Work

September 16, 2025 by 29 Comments

If you take the wheels off a FIAT Punto, you might just notice that those rims fit nicely on a rail. [AT Lab] did, and the resulting build makes for a very watchable video.

Some of us have been known to spend a little too much time chasing trains, and there’s little on rails that won’t catch a railfan’s eye. That goes for rail speeders too, home constructed railcarts for exploring abandoned lines, and there are some great builds out there. We like the one in the video below the break, but we can’t help noticing a flaw which might just curtail its career.

It’s a simple enough build, a wooden chassis, a single motor and chain drive to one axle. All the wheel fittings are 3D printed, which might be a case of using the one tool you have to do everything, but seems to work. It rides well on the test track which appears to be an abandoned industrial siding, but it’s in those wheels we can see the problem and we guess that perhaps the builder is not familiar with rails. The Punto wheels have an inner rim and an outer rim, while a true rail wheel only has an inner one. There’s a good reason for this; real railways have points and other trackwork, not to mention recessed rails at road crossings or the like. We love the cart, but we’d cut those inner rims off to avoid painful derailments.

If you’re up for the ultimate railway build, take care not to go near a live line, and make sure you follow this video series.

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