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A Brief History Of Fuel Cells

May 22, 2025 by 13 Comments

If we asked you to think of a device that converts a chemical reaction into electricity, you’d probably say we were thinking of a battery. That’s true, but there is another device that does this that is both very similar and very different from a battery: the fuel cell.

In a very simple way, you can think of a fuel cell as a battery that consumes the chemicals it uses and allows you to replace those chemicals so that, as long as you have fuel, you can have electricity. However, the truth is a little more complicated than that. Batteries are energy storage devices. They run out when the energy stored in the chemicals runs out. In fact, many batteries can take electricity and reverse the chemical reaction, in effect recharging them. Fuel cells react chemicals to produce electricity. No fuel, no electricity.

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Field Testing An Antenna, Using A Field

May 21, 2025 by 9 Comments

The ARRL used to have a requirement that any antenna advertised in their publications had to have real-world measurements accompanying it, to back up any claims of extravagant performance. I’m told that nowadays they will accept computer simulations instead, but it remains true that knowing what your antenna does rather than just thinking you know what it does gives you an advantage. I was reminded of this by a recent write-up in which the performance of a mylar sheet as a ground plane was tested at full power with a field strength meter, because about a decade ago I set out to characterise an antenna using real-world measurements and readily available equipment. I was in a sense field testing it, so of course the first step of the process was to find a field. A real one, with cows. Continue reading “Field Testing An Antenna, Using A Field” →

Big Chemistry: Fuel Ethanol

May 21, 2025 by 73 Comments

If legend is to be believed, three disparate social forces in early 20th-century America – the temperance movement, the rise of car culture, and the Scots-Irish culture of the South – collided with unexpected results. The temperance movement managed to get Prohibition written into the Constitution, which rankled the rebellious spirit of the descendants of the Scots-Irish who settled the South. In response, some of them took to the backwoods with stills and sacks of corn, creating moonshine by the barrel for personal use and profit. And to avoid the consequences of this, they used their mechanical ingenuity to modify their Fords, Chevrolets, and Dodges to provide the speed needed to outrun the law.

Though that story may be somewhat apocryphal, at least one of those threads is still woven into the American story. The moonshiner’s hotrod morphed into NASCAR, one of the nation’s most-watched spectator sports, and informed much of the car culture of the 20th century in general. Unfortunately, that led in part to our current fossil fuel predicament and its attendant environmental consequences, which are now being addressed by replacing at least some of the gasoline we burn with the same “white lightning” those old moonshiners made. The cost-benefit analysis of ethanol as a fuel is open to debate, as is the wisdom of using food for motor fuel, but one thing’s for sure: turning corn into ethanol in industrially useful quantities isn’t easy, and it requires some Big Chemistry to get it done.
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The Make-roscope

May 20, 2025 by 11 Comments

Normal people binge-scroll social media. Hackaday writers tend to pore through online tech news and shopping sites incessantly. The problem with the shopping sites is that you wind up buying things, and then you have even more projects you don’t have time to do. That’s how I found the MAKE-roscope, an accessory aimed at kids that turns a cell phone into a microscope. While it was clearly trying to appeal to kids, I’ve had some kids’ microscopes that were actually useful, and for $20, I decided to see what it was about. If nothing else, the name made it appealing.

My goal was to see if it would be worth having for the kinds of things we do. Turns out, I should have read more closely. It isn’t really going to help you with your next PCB or to read that tiny print on an SMD part. But it is interesting, and — depending on your interests — you might enjoy having one. The material claims the scope can magnify from 125x to 400x.

What Is It?

The whole thing is in an unassuming Altoids-like tin. Inside the box are mostly accessories you may or may not need, like a lens cloth, a keychain, plastic pipettes, and the like. There are only three really interesting things: A strip of silicone with a glass ball in it, and a slide container with five glass slides, three of which have something already on them. There’s also a spare glass ball (the lens).

What I didn’t find in my box were cover slips, any way to prepare specimens, and — perhaps most importantly — clear instructions. There are some tiny instructions on the back of the tin and on the lens cloth paper. There is also a QR code, but to really get going, I had to watch a video (embedded below).

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The World Wide Web And The Death Of Graceful Degradation

May 20, 2025 by 72 Comments

In the early days of the World Wide Web – with the Year 2000 and the threat of a global collapse of society were still years away – the crafting of a website on the WWW was both special and increasingly more common. Courtesy of free hosting services popping up left and right in a landscape still mercifully devoid of today’s ‘social media’, the WWW’s democratizing influence allowed anyone to try their hands at web design. With varying results, as those of us who ventured into the Geocities wilds can attest to.

Back then we naturally had web standards, courtesy of the W3C, though Microsoft, Netscape, etc. tried to upstage each other with varying implementation levels (e.g. no iframes in Netscape 4.7) and various proprietary HTML and CSS tags. Most people were on dial-up or equivalently anemic internet connections, so designing a website could be a painful lesson in optimization and targeting the lowest common denominator.

This was also the era of graceful degradation, where us web designers had it hammered into our skulls that using and navigating a website should be possible even in a text-only browser like Lynx, w3m or antique browsers like IE 3.x. Fast-forward a few decades and today the inverse is true, where it is your responsibility as a website visitor to have the latest browser and fastest internet connection, or you may even be denied access.

What exactly happened to flip everything upside-down, and is this truly the WWW that we want?

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Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Wafer-Thin Keyboard

May 19, 2025 by 8 Comments

The mikecinq, an incredibly slim keyboard.
Image by [dynam1keNL] via reddit
But sir! I can’t believe I missed [dynam1keNL]’s initial flat offering from about a year ago, the mikefive, which came about when he and some friends ordered switches directly from Kailh and Kailh were like, do you want to try these even lower-profile PG1316 laptop switches? It’s called the mikefive because it’s 5 mm thick.

That’s okay, though, because now you’re caught up and I can talk about his latest keyboard, the mikecinq. The inspiration for this one includes the aesthetics of Le Chiffre and the slimness of Le Oeuf. As you’ll see in the gallery, the top is ever-so-slightly slanted downward from the top.

You can see it really well in the second picture — the top row is flush with the case, and the keys gradually get taller toward the thumb clusters. All [dynam1keNL] really had to do was 3D model the new case and screw in the PCB from his daily driver mikefive.

Image by [dynam1keNL] via reddit
[dynam1keNL] ultimately found it nice and comfy, especially for the thumbs, but decided to take it one step further and designed a new switch footprint. Why? The PG1316s are surface-mount with contacts below the switch, so you really need a hotplate or oven to mount them.

So in order to deal with this, he made a dedicated mikecinq PCB with big cutouts with castellated holes beneath each switch. Now, the switch contacts are accessible from underneath and can be soldered with an iron.

You may have noticed that the mikefive production files are not available on GitHub — that’s because it was recently licensed and will be available soon. But if you want production files for the mikecinq, let him know in the comments.

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