1950s Switching Power Supply Does It Mechanically

April 8, 2024 by 25 Comments

When you hear about a switching power supply, you think of a system that uses an inductor and a switch to redistribute energy from the input to the output. But the original switching power supply was the vibrator supply, which was common in automotive applications back in the middle part of the last century. [Mr. Carlson] has a 1950s-era example of one of these, and he invites us to watch him repair it in the video below.

Most of the vibrator supplies we’ve seen have been built into car radios, but this one is in a box by itself. The theory is simple. A DC voltage enters the vibrator, which is essentially a relay that has a normally-closed contact in series with its coil. When current flows, the relay operates, breaking the contact. With no magnetic field, the springy contact returns to its original position, allowing the whole cycle to repeat.

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Heating Mars On The Cheap

April 8, 2024 by 78 Comments

Mars is fairly attractive as a potential future home for humanity. It’s solid, with firm land underfoot. It’s able to hang on to a little atmosphere, which is more than you can say about the moon. It’s even got a day/night cycle remarkably close to our own. The only problem is it’s too darn cold, and there’s not a lot of oxygen to breathe, either.

Terraforming is the concept of fixing problems like these on a planet-wide scale. Forget living in domes—let’s just make the whole thing habitable!

That’s a huge task, so much current work involves exploring just what we could achieve with today’s technology. In the case of Mars, [Casey Handmer] doesn’t have a plan to terraform the whole planet. But he does suggest we could potentially achieve significant warming of the Red Planet for $10 billion in just 10 years. Continue reading “Heating Mars On The Cheap” →

Fortran And WebAssembly: Bringing Zippy Linear Algebra To NodeJS & Browsers

April 8, 2024 by 15 Comments

With the rise of WebAssembly (wasm) it’s become easier than ever to run native code in a browser. As mostly just another platform to target, it would be remiss if Fortran was not a part of this effort, which is why a number of projects have sought to get Fortran supported on wasm.

For the ‘why’, [George Stagg] makes the point that software packages like BLAS and LAPACK for Fortran are still great for scientific computing, while the ‘how’ is a bit more hairy, but getting better courtesy of the still-in-development LLVM front-end for Fortran (flang-new). Using it for wasm is not straightforward yet, due to the lack of a wasm32 target, but as [George] demonstrates, this is easily patched around.

We reported on Fortran and wasm back in 2016, with things having changed somewhat in the intervening eight years (yes, that long). The Fortran-to-C translator utility (f2c) is effectively EOL, while LFortran is coming along but still missing many features. The Dragonegg GCC-frontend-for-LLVM project was the best shot in 2020 for Fortran and WebAssembly, but obsolete now. Classic Flang has been in LLVM for a while, but is to be replaced with what is now called flang-new. The wish by [George] is now to find a way to get his patched flang-new code for wasm support into the project.

In the article, the diff for patching the flang-new toolchain to target wasm is provided. During compilation of the standard Fortran runtime it was then found that the flang-new code assumes that target system sizeof() results are identical to those of the host system, which of course falls flat for wasm32. One more patch (or hardcoded hack, rather) later the ‘Hello World’ example in Fortran was up and running, clearing the way to build the BLAS (Basic Linear Algebra Subprograms) and LAPACK (Linear Algebra Package) libraries and create a few example projects in Fortran-for-wasm32 which uses them.

The advantage of being able to use extremely well-optimized software packages like these when limited to a browser environment should be obvious, in addition to the benefit of using existing codebases. It is certainly [George]’s hope that flang-new will soon officially support wasm (32 and 64-bit) as targets, and he actively seeks help with making this a reality.

KanaChord Is A Macro Pad For Japanese Input

April 8, 2024 by 13 Comments

There are various situations that warrant additional keyboards on your desk, and inputting a second language is definitely a good one. That’s the idea behind KanaChord, which generates Unicode macros to render Japanese Kana characters using chords — pressing multiple keys at once as you would on a piano.

The Japanese writing system is made up of Kanji (Chinese characters), Hirigana, and Katakana. Without going into it too much, just know that Hirigana and Katakana are collectively known as the Kana, and there’s a table that lays out the pairing of vowels and consonants. To [Mac Cody], the layout of the Kana table inspired this chording keyboard.

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Fixing An Expensive Smart Toaster Is Worth The Time

April 7, 2024 by 49 Comments

There was a time when the simplest and cheapest kitchen appliance you could think of was a toaster. Some nichrome wire, a spring, and a mechanical thermostat were all you needed. Those days are gone and today’s toasters are full of special features, network connections, and fancy cases.

Take [boilerbot]’s Breville die-cast smart toaster. The four-slice model is upwards of $200. As Star Trek’s [Mr. Scott] said, “The more they overthink the plumbing, the easier it is to stop up the drain.” That seems to be the case here. The toaster failed and while [boilerbot] did fix it, he got lucky. He mentions that if the damage had been lower in the toaster, getting to it would have been nearly impossible.

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A Spark Gap Transmitter, Characterized

April 7, 2024 by 31 Comments

When we think of a spark gap radio transmitter, most of us immediately imagine an early twentieth century ship’s radio room or similar. Most of us know these transmitters as the first radio systems, and from there we’ll probably also know that they were phased out when better circuits arrived, because of their wide bandwidth. So it’s rare in 2024 to find anyone characterizing a spark gap transmitter, as [Baltic Lab] has.

The circuit is simple enough, a high voltage passes through an RC network to a spark gap, the other side of which is a tuned circuit. The RC network and the spark gap form a simple low frequency relaxation oscillator, with the C being charged until the spark gap triggers, forcing the subsequent discharge of the capacitor and causing the spark to extinguish and the cycle to repeat. The resulting chain of high voltage pulses repeatedly energizes the tuned circuit, with each pulse causing a damped oscillation at its resonant frequency. The resulting RF signal is a crude AM tone which can be received fairly simply.

The mathematics behind it all is pretty interesting, revealing both the cause of the bandwidth spread in the low Q factor of the tuned circuit, and the presence of a large spurious frequency spike on an interaction with the capacitor in the RC circuit. It’s all in the video below the break, and we have to admit, it taught us something about radio we didn’t know.

Meanwhile spark gaps weren’t the only early radio transmitter technology. How about an alternator?

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Hackaday Links: April 7, 2024

April 7, 2024 by 12 Comments

Folks with a bit of knowledge about network security commonly use virtual private networks (VPNs) when out and about. Whether you’re connecting to public WiFi or somebody passes you a questionable Ethernet cable at a hacker con, it’s nice to have a secure endpoint to tunnel all of your traffic. As a secondary bonus, connecting through a VPN can obscure your physical location. It’s that second feature that has a bunch of people jumping on the VPN bandwagon as they try to dodge the recent porn age checks that have gone into effect in a number of states. According to a recent article in PopSci, one particular VPN provider saw a 275% jump in demand on the same day that PornHub cut off access to users in Texas. While the debate over underage users accessing adult content is far outside of our wheelhouse, anything that gets more users connecting to the Internet via encrypted means is arguably a net positive.

If you wanted somebody from the Geek Squad to set up that VPN so you can get back on PornHub to work securely from the local coffee shop, you might be out of luck. Reports have been coming in that Best Buy’s mobile nerd division is seeing sweeping layoffs. Geeks were told to stay home on Tuesday and await a call from corporate, at which point many got the surprising news that they no longer had a job. The /r/GeekSquad subreddit has been a rallying point for staff who got the axe, with the user [jaym026] posting what we assume is an AI-generated inspirational speech from Optimus Prime. Of course, it sucks for anyone to lose their job, especially with the way things are these days. Still, we’re willing to bet almost none of those affected will look back on the day they were let go from an increasingly irrelevant brick-and-mortar electronics store as a low point in their professional careers.

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