Author: Brian Benchoff

5252 Articles

Hackaday Links Column Banner

Hackaday Links: February 24, 2019

February 24, 2019 by 20 Comments

Back To The Future Part II, released in 1989, told us the far-off future of 2015 would have flying cars, drones working for national newspapers, and self-lacing sneakers. Our best hope for flying cars is Uber, and that’s going to be hilarious when it fails. (Note to Uber: buy KSMO, Santa Monica airport, as an air taxi hub because that’s the most hilarious of all possible realities.) National newspapers — heck, even newspapers — don’t exist anymore. Self-lacing sneakers? Nike’s self-lacing sneakers brick themselves with a firmware update. Don’t worry, it’s only the left shoe.

HackSpace magazine Vol. 16 is out, and there’s a few pages dedicated to Tindie from the person who runs it, our fabulous [Jasmine]. There’s some good tips in here for Tindie sellers — especially shipping — and a good introduction to what Tindie actually is. The three-second elevator pitch of, ‘Etsy but for DIY electronics’ is not in the feature, though.

Is it duct tape or duck tape? That’s a silly question, because it’s ‘duck’ tape, but that’s not important. Gaffer tape is superior. [Ross Lowell], the inventor of gaffer tape, passed away last week at the age of 92.

[Peter Stripol] has a hobby of building ultralights in his basement. Actually, he has a hangar now, so everything’s good. His first two planes flew as Part 103 ultralights, however, there were design problems. [Peter] is using an electric powerplant, with motors and batteries, which is much lighter than a gas-chugging Rotax. However, he was still basing his designs on traditional ultralights. His now third build will be slightly more trimmed down, probably a little bit faster, and might just use 3D-printed control surfaces. Check out the intro to the mk3 airplane here.

[Matthias Wandel], the woodworking Canadian famous for designing the pantorouter, just built a three-legged stool. Sure, that doesn’t sound impressive, but check this out. All the weird mortises were done on the pantorouter, and there are some weird mortises here.

You’re only cool if you got chainz, so here’s some PCB chainz. This was done by [@jeffwurz] with OSHPark PCBs. The design, from as far as we can tell, is simple. It’s just a PCB without a soldermask, and a small cutout in one of the links. Assemble it into a chain, and if you’re clever, solder some resistor leads across the gap to make it a bit more solid.

ASMR, or officially, ‘autonomous sensory meridian response’, is the tingling sensation moving down your back induced by specific auditory (or visual) stimuli. That’s the scientific definition. On the Internet, it’s people breathing into microphones and smacking their lips. Yes, there are videos of this. Thousands of them. There are 11-year-old girls raking in the YouTube money posting ASMR videos. It’s weird and gross, and don’t get me started on slime videos. You’ve also got unboxing videos. The Raspberry Pi foundation found a way to combine ASMR with unboxing videos. I gotta respect the hustle here; ASMR and unboxing videos are some of the most popular content available, and the Pi foundation is not only combining the two, but doing so ironically. It’s exactly the content everyone wants to see, and it’ll bring in people who hate ASMR and unboxing videos. Someone over at the Pi foundation really knows what they’re doing here.

Curve Tracing On Spray Painted CRTs

February 24, 2019 by 16 Comments

A Lissajous curve is formed when two sine waves plotted on their respective X and Y axes. You can see one using an oscilloscope and a couple of signal generators, if you play with one of those ‘pendulums tracing in the sand’ toys, or if you really need something sciencey for your home decor you can trace them out with a disassembled CRT. That’s what [Emily] did with the LissaJukebox. It traces curves. No, it’s not a curve tracer, that’s another tool altogether

If you’re going to put squigglies on a CRT, you obviously need a CRT, and it needs to look good. There are a few options out there, from old oscilloscope tubes, the CRTs found in old VHS camcorders, to tiny electrostatic tubes that are slightly easier to drive. For this build, [Emily] chose an old, bog-standard, black and white television. But the screen is green, right? Yeah, but if you carefully mask off a CRT and buy some stained glass spray paint, a CRT can be any color you want. Except for purple, the purple stained glass spray paint didn’t work for some reason.

To generate the various functions, [Emily] used an XR2206 function generator, sold in kit form on Amazon, eBay, and various other online retailers for a pittance. One of these function generators controls the X axis, another the Y, and both of these generators are fed into a 15 Watt stereo amplifier board to run the deflection coils in the CRT. If you’re following along at home, yes, this is dangerous. Don’t touch the CRT or it will stop your heart. Those of us whose hearts are as black as coal are safe.

There were a few modifications needed to turn the XR2206 function generator ‘kit’ into something a bit more useful for this project. The through-hole pots were replaced with panel-mount pots, and the range/amplitude setting is now controlled with a rotary switch.

Is it useful? Well, actually, if you’re building a set for a TV show and you need something that looks ‘sciencey’, a LissaJukebox should be right up your alley. Other than that it looks pretty, and we now know there’s a spray paint that will turn your old, boring black and white CRT into a glorious amber phosphor. Can’t beat that.

The PC Speaker Lives On As A New Album

February 23, 2019 by 25 Comments

The speaker in the original IBM PC is nearly the worst electronic musical instrument ever created. This isn’t because amazing works of art were never created for the PC speaker; no, that’s been done, and it’s amazing. The PC speaker is terrible because of how limited it is. It does one note at a time, only square waves, driven by an 8253 Programmable Interval Timer. Polyphony? Forget about it. Volume control? Nope. These aren’t really shortcomings, because music is art, and you can write a novel without using the letter ‘E’; the trick is in how you manage to do it.

[shiru8bit] took a deep dive into the PC speaker and decided to make an album. The video, with the completely necessary CRT graphic display, can be seen here. This alone is impressive, but what makes it amazing is how this album happened.

If you want to play more than a simple melody on a PC speaker, there are two or two and a half ways to do it. The first is to (virtually) set up two (or more) channels, loaded up with frequency values. At set intervals, the CPU changes the 8253 to output one frequency, then in the next chunk of time, sets the 8253 to another frequency. It sounds ‘bubbly’ for lack of a better term, but the results can be amazing; just check out the PC speaker version of Monkey Island. The 8253 can also be turned into a rudimentary DAC, but this was a rare technique thanks to patents, and by the time the patents expired everyone already had a Soundblaster. Oh well.

[shiru8bit]’s album uses the first technique, cycling through monophonic square waves at 120 Hz, but the real trick here is how the individual channels were composed. This required creating a VSTi plugin called PCSPE. This emulates a PC speaker, and sort of, kind of, implements arpeggios, pitch, and priority of different channels. Effectively, it’s a PC Speaker tracker.

The result is classic chiptune goodness, made on an instrument that really shouldn’t be used for music. It can be played on DosBox, but the weirdness of the real hardware including transients and the inefficiencies of a tiny speaker make real hardware almost a necessity here. You can check out the entire album below.

Continue reading “The PC Speaker Lives On As A New Album” →

Cheaply Charging Cylindrical Cells

February 19, 2019 by 15 Comments

For one reason or another, a lot of us have a bunch of 18650 cells sitting around. Whether they’re for flashlights, our fancy new vape pen, remote controlled toys, or something more obscure, there is a need to charge a bunch of lithium ion cells all at once. This project, by [Daren Schwenke], is the way to do it. It’ll charge ten 18650 cells quickly using a stock ATX power supply and less than twenty bucks in Amazon Prime parts.

The idea began when [Daren] realized his desktop lithium ion charger took between 4-6 hours to fully charge two 18650 cells. With a Mountainboard project, or a big ‘ol electric skateboard waiting in the wings, [Daren] realized there had to be a better solution to charging a bunch of 18650 cells. There is, and it’s those twenty bucks at Amazon and a few 3D printed parts.

The relevant parts are just a ten-pack of 18650 cell holders (with PC pins) and a ten-pack of 5V, 1A charging modules (non-referral Amazon link, support truly independent journalism) meant to be the brains of a small USB power bank. These parts were wired up to the 5V rail of a discarded ATX power supply (free, because you can scavenge these anywhere, and everything was wrapped up with a neat little 3D printed mount.

Is this the safest way to charge lithium ion cells? No, because you can build a similar project with bailing wire. There is no reverse polarity protection, and if there’s one thing you never want to do, it’s reverse the polarity. This is, however, a very effective and very cheap solution to charging a bunch of batteries. It does what it says it’ll do, nothing more.

WiFi Hides Inside A USB Cable

February 18, 2019 by 42 Comments

If you weren’t scared of USB cables before, you should be now. The O.MG cable (or Offensive MG kit) from [MG] hides a backdoor inside the shell of a USB connector. Plug this cable into your computer and you’ll be the victim of remote attacks over WiFi.

You might be asking what’s inside this tiny USB cable to make it susceptible to such attacks. That’s the trick: inside the shell of the USB ‘A’ connector is a PCB loaded up with a WiFi microcontroller — the documentation doesn’t say which one — that will send payloads over the USB device. Think of it as a BadUSB device, like the USB Rubber Ducky from Hak5, but one that you can remote control. It is the ultimate way into a system, and all anyone has to do is plug a random USB cable into their computer.

In the years BadUSB — an exploit hidden in a device’s USB controller itself — was released upon the world, [MG] has been tirelessly working on making his own malicious USB device, and now it’s finally ready. The O.MG cable hides a backdoor inside the shell of a standard, off-the-shelf USB cable.

The construction of this device is quite impressive, in that it fits entirely inside a USB plug. But this isn’t a just a PCB from a random Chinese board house: [MG] spend 300 hours and $4000 in the last month putting this project together with a Bantam mill and created his own PCBs, with silk screen. That’s impressive no matter how you cut it.

Future updates to this cable that will hack any computer might include a port of ESPloitV2, an Open Source WiFi controlled USB HID keyboard emulator. That will bring a lot of power to this device that’s already extremely capable. In the video attached to this tweet you can see the O.MG cable connected to a MacBook, with [MG] opening up a webpage remotely.

Travelling The Oregon Trail With An Apple II Robot

February 18, 2019 by 5 Comments

For one reason or another, we’re going with a retro-futuristic 80s aesthetic in this case, [Mike] decided to turn an Apple IIe into a robot. If you have to ask why, you’ll never know, but this project does have some interesting things going for it. There’s a voice synthesizer, a brand spankin’ new power supply, and it rolls around on the floor thanks to Apple BASIC.

Since this is a mobile robot, there needs to be a power supply in there somewhere. The Apple II had a fantastic switching power supply, but it ran off mains voltage. To make this Apple run off a 14.8 V LiPO battery, [Mike] needed to re-engineer this power supply to give +5, +12, -5, and -12 Volts. The easiest is the positive voltage, and for that, he used a big ‘ol LM1084 linear regulator for the +5 V line. This outputs a ton of heat and probably isn’t the best solution, but it is a solution that works. The +12 line was again another linear regulator, an LM7812CV. Since this is dropping 14.8 V down to 12, the efficiency isn’t that bad, and since there’s no floppy drive it’s not pulling much current anyway. The negative voltages are a MAX764 / MAX765 inverting switching regulators. This completely replaces the original power supply in the Apple II, and is a decent reference design for anyone who wants to make a luggable Apple II laptop.

To move this thing around, the motors run on their own 11.1 V LiPO, with a bunch of Pololu gear tying everything together. The BASIC code was written on an emulator, transferred over with the Floppy Emu. Movement is controlled through the output pins on the joystick port, and there’s a text to speech module that was obviously needed and ties this project together wonderfully. You can check out the video demo of the build below.

Continue reading “Travelling The Oregon Trail With An Apple II Robot” →

Hackaday Links Column Banner

Hackaday Links: February 17, 2019

February 17, 2019 by 43 Comments

There is a population of retrocomputing enthusiasts out there, whose basements, garages, and attics have been taken over by machines of years past. Most of the time, these people concentrate on one make; you’re an Apple guy, or you’re a Commodore guy, or you’re a Ford guy, or you’re a Chevy guy. The weirdos drive around with an MSX in the trunk of an RX7. This is the auction for nobody. NASA’s JPL Lab is getting rid of several tons of computer equipment, all from various manufacturers, and not very ‘vintage’ at all. Check out the list. There are CRT monitors from 2003, which means they’re great monitors that weigh as much as a person. There’s a lot of Sun equipment. If you’ve ever felt like cleaning up a whole bunch of trash for JPL, this is your chance. Grab me one of those sweet CRTs, though.

Last week, we published something on the ‘impossible’ tech behind SpaceX’s new engine. It was reasonably popular — actually significantly popular — and got picked up on Hacker News and one of the Elon-worshiping subreddits. Open that link in one tab. Now, open this link in another. Read along as a computer voice reads Hackaday words, all while soaking up YouTube ad revenue. What is our recourse? Does this constitute copyright infringement? I dunno; we don’t monetize videos on YouTube. Thanks to [MSeifert] for finding this.

Wanna see something funny? Check out the people in the comments below who are angry at a random YouTuber stealing Hackaday content, while they have an ad blocker on.

Teenage Engineering’s OP-1 is back in production. What is it and why does it matter? The OP-1 is a new class of synthesizer and sampler that kinda, sorta looks like an 80s Casio keyboard, but packed to the gills with audio capability. At one point, you could pick one of these up for $800. Now, prices are at about $1300, simply because production stopped for a while (for retooling, we’re guessing) and the rumor mill started spinning. The OP-1 is now back in production with a price tag of $1300. Wait. What? Yes, it’s another case study in marketing: the best way to find where the supply and demand curves cross is to stop production for a while, wait for the used resellers to do their thing, and then start production again with a new price tag that people are willing to pay. This is Galaxy Brain-level business management, people.

What made nerds angry this week? Before we get to that, we’re gonna have to back track a bit. In 2016, Motherboard published a piece that said PC Gaming Is Still Way Too Hard, because you have to build a PC. Those of us in the know realize that building a PC is as simple as buying parts and snapping them together like an expensive Lego set. It’s no big deal. A tech blog, named Motherboard, said building a PC was too hard. It isn’t even a crack at the author of the piece at this point: this is editorial decay.

And here we are today. This week, the Internet reacted to a video from The Verge on how to build a PC. The original video has been taken down, but the reaction videos are still up: here’s a good one, and here’s another. Now, there’s a lot wrong with the Verge video. They suggest using a Swiss army knife for the assembly, hopefully one with a Philips head screwdriver. Philips head screwdrivers still exist, by the way. Dual channel RAM was completely ignored, and way too much thermal compound was applied to the CPU. The cable management was a complete joke. Basically, a dozen people at The Verge don’t know how to build a PC. Are the criticisms of incompetence fair? Is this like saying [Doug DeMuro]’s car reviews are invalid because he can’t build a transmission or engine, from scratch, starting from a block of steel? Ehhh… we’re pretty sure [Doug] can change his own oil, at least. And he knows to use a screwdriver, instead of a Swiss army knife with a Philips head. In any event, here’s how you build a PC.

Hackaday writers to be replaced with AI. Thank you [Tegwyn] for the headline. OpenAI, a Musk and Theil-backed startup, is pitching a machine learning application that is aimed at replacing journalists. There’s a lot to unpack here, but first off: this already exists. There are companies that sell articles to outlets, and these articles are produced by ‘AI’. These articles are mostly in the sports pages. Sports recaps are a great application for ML and natural language processing; the raw data (the sports scores) are already classified, and you’re not looking for Pulitzer material in the sports pages anyway. China has AI news anchors, but Japan has Miku and artificial pop stars. Is this the beginning of the end of journalism as a profession, with all the work being taken over by machine learning algorithms? By vocation, I’m obligated to say no, but I have a different take on it. Humans can write better than AI, and the good ones are nearly as fast. Whether or not the readers care if a story is accurate or well-written is another story entirely. It will be market forces that determine if AI journalists take over, and if you haven’t been paying attention, no one cares if a news story is accurate or well written, only if it caters to their preexisting biases and tickles their confirmation bias.

Of course, you, dear reader, are too smart to be duped by such a simplistic view of media engagement. You’re better than that. You’re better than most people, in fact. You’re smart enough to see that most media is just placating your own ego and capitalizing on confirmation bias. That’s why you, dear reader, are the best audience. Please like, share, and subscribe for more of the best journalism on the planet.