Tech In Plain Sight: Eyeglasses

Glasses wearers, try a little experiment. Take off your glasses and look at this page or, at least, at something you can’t see well without your glasses. Now imagine if you lived in a time where there was nothing to be done about your vision. If you wear contacts or you have good vision — perhaps you had surgery — then congratulations. But for most of us, vision changes with age are a fact of life. Even many young people need glasses or some other intervention to get good eyesight. At first glance, you might think eyeglasses are an obvious invention, but it turns out we didn’t get real glasses for quite some time and modern glasses are truly a piece of high tech that hides — quite literally — right in front of your face.

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Mining And Refining: Pure Silicon And The Incredible Effort It Takes To Get There

Were it not for the thin sheath of water and carbon-based life covering it, our home planet would perhaps be best known as the “Silicon World.” More than a quarter of the mass of the Earth’s crust is silicon, and together with oxygen, the silicate minerals form about 90% of the thin shell of rock that floats on the Earth’s mantle. Silicon is the bedrock of our world, and it’s literally as common as dirt.

But just because we have a lot of it doesn’t mean we have much of it in its pure form. And it’s only in its purest form that silicon becomes the stuff that brought our world into the Information Age. Elemental silicon is very rare, though, and so getting appreciable amounts of the metalloid that’s pure enough to be useful requires some pretty energy- and resource-intensive mining and refining operations. These operations use some pretty interesting chemistry and a few neat tricks, and when scaled up to industrial levels, they pose unique challenges that require some pretty clever engineering to deal with.

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A close-up view of surface-mount components on a circuit board

Smaller Is Sometimes Better: Why Electronic Components Are So Tiny

Perhaps the second most famous law in electronics after Ohm’s law is Moore’s law: the number of transistors that can be made on an integrated circuit doubles every two years or so. Since the physical size of chips remains roughly the same, this implies that the individual transistors become smaller over time. We’ve come to expect new generations of chips with a smaller feature size to come along at a regular pace, but what exactly is the point of making things smaller? And does smaller always mean better?

Smaller Size Means Better Performance

Over the past century, electronic engineering has improved massively. In the 1920s, a state-of-the-art AM radio contained several vacuum tubes, a few enormous inductors, capacitors and resistors, several dozen meters of wire to act as an antenna, and a big bank of batteries to power the whole thing. Today, you can listen to a dozen music streaming services on a device that fits in your pocket and can do a gazillion more things. But miniaturization is not just done for ease of carrying: it is absolutely necessary to achieve the performance we’ve come to expect of our devices today. Continue reading “Smaller Is Sometimes Better: Why Electronic Components Are So Tiny”

The Pi Zero 2 W Is The Most Efficient Pi

Last week we saw the announcement of the new Raspberry Pi Zero 2 W, which is basically an improved quad-core version of the Pi Zero — more comparable in speed to the Pi 3B+, but in the smaller Zero form factor. One remarkable aspect of the board is the Raspberry-designed RP3A0 system-in-package, which includes the four CPUs and 512 MB of RAM all on the same chip. While 512 MB of memory is not extravagant by today’s standards, it’s workable. But this custom chip has a secret: it lets the board run on reasonably low power.

When you’re using a Pi Zero, odds are that you’re making a small project, and maybe even one that’s going to run on batteries. The old Pi Zero was great for these self-contained, probably headless, embedded projects: sipping the milliamps slowly. But the cost was significantly slower computation than its bigger brothers. That’s the gap that the Pi Zero 2 W is trying to fill. Can it pull this trick off? Can it run faster, without burning up the batteries? Raspberry Pi sent Hackaday a review unit that I’ve been running through the paces all weekend. We’ll see some benchmarks, measure the power consumption, and find out how the new board does.

The answer turns out to be a qualified “yes”. If you look at mixed CPU-and-memory tasks, the extra efficiency of the RP3A0 lets the Pi Zero 2 W run faster per watt than any of the other Raspberry boards we tested. Most of the time, it runs almost like a Raspberry Pi 3B+, but uses significantly less power.

Along the way, we found some interesting patterns in Raspberry Pi power usage. Indeed, the clickbait title for this article could be “We Soldered a Resistor Inline with Raspberry Pis, and You Won’t Believe What Happened Next”, only that wouldn’t really be clickbait. How many milliamps do you think a Raspberry Pi 4B draws, when it’s shut down? You’re not going to believe it.

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Photo of an arid desert landscape

How Practical Is Harvesting Water From The Air?

Water is one of the most precious substances required to sustain human life. Unfortunately, in some areas like California, it’s starting to run out.

The ongoing drought has some people looking towards alternative solutions, such as sucking water out of the very air itself. In particular, a company called Tsunami Products has been making waves in the press with its atmospheric water generators, touting them as a solution for troubled drought-stricken areas, as reported by AP News. Today, we’ll look at how these machine capture water, and whether or not they can help in areas short on water.

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Can We Repurpose Old Wind Turbine Blades?

Wind turbines are a fantastic, cheap, renewable source of energy. However, nothing lasts forever, and over time, the blades of wind turbines fatigue and must be replaced. This then raises the question of what to do with these giant waste blades. Thankfully, a variety of projects are exploring just those possibilities.

A Difficult Recycling Problem

Around 85% of a modern wind turbine is recyclable. The problem is that wind turbine blades currently aren’t. The blades last around 20 to 25 years, and are typically made of fiberglass or carbon fiber. Consisting of high-strength fibers set in a resin matrix, these composite materials are incredibly difficult to recycle, as we’ve discussed previously. Unlike metals or plastics, they can’t just be melted down to be recast as fresh material. Couple this with the fact that wind turbine blades are huge, often spanning up to 300 feet long, and the problem gets harder. They’re difficult and expensive to transport and tough to chop up as well.

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Decoding SMD Part Markings

You’ve probably encountered this before — you have a circuit board that is poorly documented, and want to know the part number of a tiny SMD chip. Retro computer enthusiast [JohnK] recently tweeted about one such database that he recently found, entitled The Ultimate SMD Marking Codes Database. This data base is only a couple of years old judging from the Wayback Machine, but seems to be fairly exhaustive and can be found referenced in quite a few electronics forums.

Unlike their larger SMD siblings, these chips in question are so small that there is no room to print the entire part number on the device. Instead, the standard practice is for manufacturers use an abbreviated code of just a few characters. These codes are only unique to each part or package, and aren’t necessarily unique across an entire product line. And just because it is standard practice does not imply the marking codes themselves follow any standard whatsoever. This seemingly hodgepodge system works just fine for the development, procurement and manufacturing phases of a product’s lifecycle. It’s during the repair, refurbishment, or just hacking for fun phases where these codes can leave you scratching your head.

Several sites like the one [JohnK] found have been around for years, and adding yet another database to your toolbox is a good thing. But none of them will ever be exhaustive. There’s a good reason for that — maintaining such a database would be a herculean task. Just finding the part marking information for a known chip can be difficult. Some manufacturers put it clearly in the data sheet, and some refer you to other documentation which may or may not be readily available. And some manufacturers ask you to contact them for this information — presumably because it is dynamic changes from time to time. Continue reading “Decoding SMD Part Markings”