Congratulations To Our Op-Amp Challenge Winners!

June 21, 2023 by Elliot Williams 15 Comments

The real world is analog, and the op-amp is the indispensable building block of many analog circuits. We wanted to give you analog fanatics out there a chance to shine and to encourage our digital brothers and sisters to dip their toes in the murky waters where ones and zeroes define the ends of a spectrum rather than representing the only choice. Hence, we presented the Op Amp Challenge. And you did not disappoint!

We received 83 entries, and it was extraordinarily hard to pick the winners. But since we had three $150 DigiKey shopping sprees to give away, our six judges buckled down and picked their favorites. Whether or not you’ve got the Golden Rules of the ideal op-amp tattooed on your arm, you’ll enjoy looking through all of the projects here. But without further ado…

The Winners

[Craig]’s Op Art is an X-Y voltage generator to plug into an oscilloscope and make classic Lissajous and other spirograph-like images, and it’s all done in analog. Maybe it was his incredible documentation, the nice use of a classic three-op-amp tunable oscillator, or the pun hidden in the title. Whatever the case, it wowed our judges and picked up a deserved place in the top three.

Hearkening back to the pre-digital dinosaur days, [Rainer Glaschick]’s Flexible Analog Computer is a modular analog computer prototyping system on a breadboard backplane. Since you have to re-wire up an analog computer for your particular, it’s great that [Rainer] gave us a bunch of examples on his website as well, including a lunar lander and classic Lorenz attractor demos.

And there was no way that [Chris]’s interactive analog LED wave array wouldn’t place in the top three. It’s a huge 2D analog simulation that runs entirely on op-amps, sensing when your hand moves across any part of its surface and radiating waves out from there. You have to admire the massive scale here, and you simply must check out the video of it in action. Glorious!

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Cottonization: Making Hemp And Flax Fibers Into The Better Cotton

June 20, 2023 by Maya Posch 16 Comments

These days it’s hard to imagine that fabrics were ever made out of anything other than cotton or synthetic fibers, yet it wasn’t too long ago that hemp and flax-based fabrics — linen — were the rule rather than the exception. Cotton production has for centuries had the major disadvantages of requiring a lot of water and pesticides, and harvesting the cotton was very labor-intensive, making cotton rather expensive. In order to make separating the cotton fibers from the seed easier, improved versions of the cotton gin (‘cotton engine’) were developed, with the 19th century’s industrial revolution enabling a fully automated version.

What makes cotton attractive is the ease of processing these fibers, which are part of the seed pod. These fibers are 25 mm – 60 mm long, 12 μm – 45 μm fine fibers that can be pulled off the seeds and spun into yarn or whatever else is needed for the final product, much like wool. Hemp and flax fibers, in contrast, are extracted from the plant stem in the form of bast fibers. Rather than being pure cellulose, these fibers are mostly a mixture of cellulose, lignin, hemicellulose and pectin, which provide the plant with rigidity, but also makes these fibers coarse and stiff.

The main purpose of cottonization is to remove as much of these non-cellulosic components as possible, leaving mostly pure cellulose fibers that not only match the handleability of cotton fibers, but are also generally more durable. Yet cottonization used to be a long and tedious process, which made bast fiber-based textiles expensive. Fortunately, the steam explosion cottonization method that we’ll be looking at here may be one of the methods by which the market will be blown open for these green and durable fibers.

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Review: InfiRay P2 Pro Thermal Camera

June 19, 2023 by Tom Nardi 65 Comments

It probably won’t surprise you to learn that Hackaday is constantly hounded by companies that want us to review their latest and greatest gadget. After all, getting us to post about their product is cheaper, easier, and arguably more effective than trying to come up with their own ad campaign. But if you’ve been with us for awhile, you’ll also know that in-house reviews aren’t something we actually do very often.

The reason is simple: we’re only interested in devices or products that offer something useful or unique to this community. As such, the vast majority of these offers get ignored. I’ll give you an example. For whatever reason, multiple companies have been trying desperately to send me electric bikes with five-figure price tags this year. But since there’s no obvious way to turn that into useful content for the readers of Hackaday, I’m still stuck pedaling myself around like it’s the 1900s. I kid of course…I haven’t dared to get on a bike in a decade.

So I don’t mind telling you that, when InfiRay contacted me about reviewing their P2 Pro thermal camera, the email very nearly went into the trash. We’ve seen these kind of phone-based thermal cameras before, and it seemed to be more of the same. But after taking a close look at the specs, accessories, and claims laid out in the marketing material, I thought this one might be worth checking out first-hand.

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The Simplest Social Engineering Hack Of Them All

June 15, 2023 by Jenny List 62 Comments

Here at Hackaday we cover news and interesting features for the hacker community, with an emphasis more on the hardware side. Nevertheless we also cover stories from time to time from the broader world of security. These usually involve vulnerabilities discovered through the patient work of software or hardware researchers, and are certainly what we’d call hacking. But what about those information security breaches that aren’t hacks like that at all? What happens when the person being breached simply gives you the information?

I’ve got one, and while it’s Not A Hack, it’s definitely something that we and those outside our community need to talk about. I’m talking about the depressingly common occurrence of organisations who should know better, gifting their letterhead to all and sundry in the form of freely editable Word documents. Continue reading “The Simplest Social Engineering Hack Of Them All” →

Spy Tech: Unshredding Documents

June 12, 2023 by Al Williams 38 Comments

Bureaucracies generate paper, usually lots of paper. Anything you consider private — especially anything that could get you in trouble — should go in a “burn box” which is usually a locked trash can that is periodically emptied into an incinerator. However, what about a paper shredder? Who hasn’t seen a movie or TV show where the office furiously shreds papers as the FBI, SEC, or some other three-letter-agency is trying to crash the door down?

That might have been the scene in the late 1980s when Germany reunified. The East German Ministry of State Security — known as the Stasi — had records of unlawful activity and, probably, information about people of interest. The staff made a best effort to destroy these records, but they did not quite complete their task.

The collapsing East German government ordered documents destroyed, and many were pulped or burned. However, many of the documents were shredded by hand, stuffed into bags, and were awaiting final destruction. There were also some documents destroyed by the interim government in 1990. Today there are about 16,000 of these bags remaining, each with 2,500 to 3,000 pieces of pages in them.

Machine-shredded documents were too small to recover, but the hand-shredded documents should be possible to reconstruct. After all, they do it all the time in spy movies, right? With modern computers and vision systems, it should be a snap.

You’d think so, anyway.

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This Weekend: VCF Swap Meet In Wall, NJ

June 9, 2023 by Tom Nardi 4 Comments

There was a time where you could regularly find local swap meets to pick up computer hardware, ham radios, and other tech gear at the sort of cut-rate prices so often produced by a sense of camaraderie. But with the rise of websites like Craigslist and eBay, meeting up in person to buy and sell used hardware started to fall out of style. The fact that the prices had to go up due to the considerable cost of shipping such large and heavy objects was an unfortunate side-effect, but it wasn’t enough to stem the tide.

It’s unlikely that we’ll ever truly return to those early days. But if you’re within driving distance of Wall, New Jersey, you can take a step back in time on Saturday and experience a proper swap meet in all its glory. Hosted by the Vintage Computer Federation, the modest $5 entry fee goes to help support their worthy goal of preserving vintage computing history. After the swap meet officially wraps up at 2 PM, a short walk will take you over to their permanent exhibit located within the sprawling InfoAge Science and History Museum.

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Radio Apocalypse: Hardening AM Radio Against Disasters

June 6, 2023 by Dan Maloney 64 Comments

If you’ve been car shopping lately, or even if you’ve just been paying attention to the news, you’ll probably be at least somewhat familiar with the kerfuffle over AM radio. The idea is that in these days of podcasts and streaming music, plain-old amplitude modulated radio is becoming increasingly irrelevant as a medium of mass communication, to the point that automakers are dropping support for it from their infotainment systems.

The threat of federal legislation seems to have tapped the brakes on the anti-AM bandwagon, at least for now. One can debate the pros and cons, but the most interesting tidbit to fall out of this whole thing is one of the strongest arguments for keeping the ability to receive AM in cars: emergency communications. It turns out that about 75 stations, most of them in the AM band, cover about 90% of the US population. This makes AM such a vital tool during times of emergency that the federal government has embarked on a serious program to ensure its survivability in the face of disaster.

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