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Hackaday Links: July 10, 2022

We always like to call out a commercial success stemming from projects that got their start on Hackaday.io, and so we’re proud to announce the release of MAKE: Calculus by Joan Horvath and Rich Cameron, a book that takes a decidedly different approach to teaching calculus than traditional courses. Geared to makers and hackers, who generally tend to have a visual style of learning, the book makes heavy use of 3D-printed models to illustrate the relationships between functions. The project started five years ago as a 2017 Hackaday Prize entry, and resulted in a talk at the 2019 Supercon. Their book is now available for preorder, and might be a great way to reacquaint themselves with calc, or perhaps even to learn it for the first time. Continue reading “Hackaday Links: July 10, 2022”

When Is One Pixel Cooler Than Millions?

On vacation, we went to see a laser show – one of the old school variety that combines multiple different lasers of many different colors together into a single beam, modulates them to create different colors, and sends it bouncing off galvos to the roof of a planetarium. To a musical score, naturally.

When I was a kid, I had no idea how they worked, but laser shows were awesome. As a younger grownup hacker, and after some friends introduced me to the dark arts, I built my own setup. I now know how they work from the deepest innards out, and they are no less awesome. Nowadays, you can get a capable set of galvos and drivers for around a hundred bucks from the far east, it’s fair to say that there’s no magic left, but the awesome still remains.

RGB laser
“laser show” by Ilmicrofono Oggiono

At the same time, lasers, and laser shows, are supremely retro. The most stunning example of this hit me while tearing apart a Casio projector ages ago to extract the otherwise unobtainable brand new 455 nm blue laser diodes. There I was pulling one diode out of an array of 24 from inside the projector, and throwing away the incredibly powerful DSP processor, hacking apart the precision optical path, and pulling out the MEMS DLP mirror array with nearly a million little mirrors, to replace it with two mirrors, driven around by big old coil-of-wire electromagnets. Like a caveman.

But still, there’s something about a laser show that I’ve never seen replicated – the insane color gamut that they can produce. It is, or can be, a lot more than just the RGB that you get out of your monitor. Some of the colors you can get out of a laser (or a prism) are simply beautiful in a way that I can’t explain. I can tell you that you can get them from combining red, blue, green, cyan, and maybe even a deep purple laser.

What you get with a laser show pales in comparison to the multi-megapixel projectors in even a normal movie theater. Heck, you’ve really got one pixel. But if you move it around fast enough, and accompany it with a decent soundtrack, you’ve still got an experience that’s worth having while you still can.

[Banner image from a positively ancient RGB laser hack. We need more! Send us yours!]

Hackaday Podcast 176: Freezing Warm Water, Hacking Lenses, Hearing Data, And Watching YouTube On A PET

It’s podcast time again, and this week Editor-in-Chief Elliot Williams sat down with Staff Writer Dan Maloney to review the best hacks on the planet, and a few from off. We’ll find out how best to capture lightning, debate the merits of freezing water — or ice cream — when it’s warm, and see if we can find out what R2D2 was really talking about with all those bleeps and bloops. Once we decode that, it’ll be time to find out what Tom Nardi was up to while the boss was away with his hidden message in episode 174, and how analog-encoded digital data survives the podcast production and publication chain. But surely you can’t watch a YouTube video on a Commodore PET, can you? As it turns out, that’s not a problem, and neither apparently is 3D printing a new ear.

The meat of Elliot’s “super secret mastering script”?  Use it on your videos too!

ffmpeg -i $infile.wav -c:v copy -af loudnorm=I=-17:LRA=5:tp=-1.5 -ar 44100 $outfile.flac

Direct download, record it to tape, and play it on your boombox.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Continue reading “Hackaday Podcast 176: Freezing Warm Water, Hacking Lenses, Hearing Data, And Watching YouTube On A PET”

This Week In Security:Breaking CACs To Fix NTLM, The Biggest Leak Ever, And Fixing Firefox By Breaking It

To start with, Microsoft’s June Security Patch has a fix for CVE-2022-26925, a Man-In-The-Middle attack against NTLM. According to NIST, this attack is actively being exploited in the wild, so it landed on the KEV (Known Exploited Vulnerabilities) Catalog. That list tracks the most important vulnerabilities to address, and triggers a mandated patch install no later than July 22nd. The quirk here is that the Microsoft Patch that fixes CVE-2022-26925 also includes a fix for a couple certificate vulnerabilities including CVE-2022-2693, Certifried. That vulnerability was one where a machine certificate could be renamed to the same as a domain controller, leading to organization-wide compromise.

The fix that rolled out in June now requires that a “strong certificate mapping” be in place to tie a user to a certificate. Having the same common name is no longer sufficient, and a secure value like the Security IDentifier (SID) must be mapped from certificate to user in Active Directory. The patch puts AD in a compatibility mode, which accepts the insecure mapping, so long as the user account predates the security certificate. This has an unintended consequence of breaking how the US Government uses CACs (Common Access Cards) to authenticate their users. Government agencies typically start their onboarding by issuing a CAC, and then establishing an AD account for that user. That makes the certificate older, which means the newest patch rejects it. Thankfully there’s a registry key that can be set, allowing the older mapping to still work, though likely with a bit of a security weakness opened up as a result. Continue reading “This Week In Security:Breaking CACs To Fix NTLM, The Biggest Leak Ever, And Fixing Firefox By Breaking It”

Retrotechtacular: 1990s CD Mastering Fit For A King

Before it was transformed into an ephemeral stream of ones and zeroes, music used to have a physical form of some kind. From wax cylinders to vinyl discs to tapes of various sizes in different housings and eventually to compact discs, each new medium was marketed as a technological leap over the previous formats, each of which justified incrementally more money to acquire.

But that’s the thing — each purchase resulted in you obtaining a physical item, which had an extensive manufacturing and distribution process behind it. And few artists demanded more manufacturing effort than Michael Jackson in his heyday, as revealed by this in-depth look at the CD manufacturing process for The King of Pop’s release of the HIStory double-disc set in 1995.

The video was produced as sort of a love letter to Michael from the staff and management of the Sony Music disc manufacturing plant in Pittman, New Jersey. The process is shown starting with the arrival of masters to the plant, strangely in the form of U-matic videocassettes; the 3/4″ continuous loop tape was normally used for analog video, but could also be used for recording digital audio. The digital audio is then sent for glass mastering, which is where the actual pits are created on a large glass disc under cleanroom conditions. In fact, much of the production process bears a strong similarity to semiconductor manufacturing, from the need for cleanrooms — although under less stringent conditions than in a fab — to the use of plasma etching, vapor deposition, and metal plating operations.

Once the master stampers are made, things really ramp up in replication. There the stamper discs go into injection molding machines, where hot polycarbonate is forced against the surface under pressure. The copies are aluminized, spin-coated with UV-cure lacquer, and sent on down the line to testing, screen printing, and packaging. Sony hired 40 extra full-time workers, who appear to have handled all the tedious manual tasks like assembling the jewel cases, to handle the extra load of this release.

As cheesy as this thank-you video may be, it was likely produced with good reason. This was a time when a Michael Jackson release was essentially a guarantee of full employment for a large team of workers. The team was able to produce something like 50,000 copies a day, and given that HIStory sold over 20 million copies, that’s a lot of workdays for the good folks at Pittman.

Continue reading “Retrotechtacular: 1990s CD Mastering Fit For A King”

The Benefits Of Displacement Ventilation

The world has been shaken to its core by a respiratory virus pandemic. Humanity has been raiding the toolbox for every possible weapon in the fight, whether that be masks, vaccinations, or advanced antiviral treatments.

As far as medicine has come in tackling COVID-19 in the past two years, the ultimate solution would be to cut the number of people exposed to the pathogen in the first place. Improving our ventilation methods may just be a great way to cut down on the spread. After all, it’s what they did in the wake of the Spanish Flu.

Continue reading “The Benefits Of Displacement Ventilation”

Linux Fu: The Browser Emacs Fusion

It is no secret that I have a few things permanently burned into my neurons: the 1802 instruction set, the commands for WordStar, and the commands for emacs. There was a time when emacs was almost my operating system. With no X11, emacs gave you a way to have a shell in one window, check your mail, and keep your work open.

I still use emacs a lot (although I’ve been getting more and more pleased with vscode with an emacs keybinding extension). But I also spend a lot of time — like right now — writing in a Web browser. Especially if I’m writing about code, it gets hard to remember which set of keys you have to use and I’ve wanted to do something about it for a long time. The answer is a very cool program called Autokey. (You can download my files for it, but you probably want to read more first.) It probably doesn’t work if you have switched to Wayland, but it can do a lot for you ranging from saving you some typing to reprogramming your favorite program to have different keystrokes. However, it isn’t without its problems, and I’ll tell you what I know about it.

The Value Proposition

Autokey sits in your system tray and it watches what you type. In its most simple usage, you can set up different phrases to substitute what you type.

For example, I might reprogram HaD to show up as Hackaday to save myself some typing. I usually use some odd character at the start or end so I don’t accidentally trigger things. So maybe I’m tired of typing or mistyping http://www.hackaday.com. I could set up ~had to automatically type the correct URL for me.

Continue reading “Linux Fu: The Browser Emacs Fusion”