Hackaday Links: January 10, 2021

You know that feeling when your previously niche hobby goes mainstream, and suddenly you’re not interested in it anymore because it was once quirky and weird but now it’s trendy and all the newcomers are going to come in and ruin it? That just happened to retrocomputing. The article is pretty standard New York Times fare, and gives a bit of attention to the usual suspects of retrocomputing, like Amiga, Atari, and the Holy Grail search for an original Apple I. There’s little technically interesting in it, but we figured that we should probably note it since prices for retrocomputing gear are likely to go up soon. Buy ’em while you can.

Remember the video of the dancing Boston Dynamics robots? We actually had intended to cover that in Links last week, but Editor-in-Chief Mike Szczys beat us to the punch, in an article that garnered a host of surprisingly negative comments. Yes, we understand that this was just showboating, and that the robots were just following a set of preprogrammed routines. Some commenters derided that as not dancing, which we find confusing since human dancing is just following preprogrammed routines. Nevertheless, IEEE Spectrum had an interview this week with Boston Dynamics’ VP of Engineering talking about how the robot dance was put together. There’s a fair amount of doublespeak and couched terms, likely to protect BD’s intellectual property, but it’s still an interesting read. The take-home message is that despite some commenters’ assertions, the routines were apparently not just motion-captured from human dancers, but put together from a suite of moves Atlas, Spot, and Handle had already been trained on. That and the fact that BD worked with a human choreographer to work out the routines.

Looks like 2021 is already trying to give 2020 a run for its money, at least in the marketplace of crazy ideas. The story, released in Guitar World of all places, goes that some conspiracy-minded people in Italy started sharing around a schematic of what they purported to be the “5G chip” that’s supposedly included in the SARS-CoV-2 vaccine. The reason Guitar World picked it up is that eagle-eyed guitar gear collectors noticed that the schematic was actually that of the Boss MetalZone-2 effects pedal, complete with a section labeled “5G Freq.” That was apparently enough to trigger someone, and to ignore the op-amps, potentiometers, and 1/4″ phone jacks on the rest of the schematic. All of which would certainly smart going into the arm, no doubt, but seriously, if it could make us shred like this, we wouldn’t mind getting shot up with it.

Remember the first time you saw a Kindle with an e-ink display? The thing was amazing — the clarity and fine detail of the characters were unlike anything possible with an LCD or CRT display, and the fact that the display stayed on while the reader was off was a little mind-blowing at the time. Since then, e-ink technology has come considerably down market, commoditized to the point where they can be used for price tags on store shelves. But now it looks like they’re scaling up to desktop display sizes, with the announcement of a 25.3″ desktop e-ink monitor by Dasung. Dubbed the Paperlike 253, the 3200 x 1800 pixel display will be able to show 16 shades of gray with no backlighting. The videos of the monitor in action are pretty low resolution, so it’s hard to say what the refresh rate will be, but given the technology it’s going to be limited. This might be a great option as a second or third monitor for those who can work with the low refresh rate and don’t want an LCD monitor backlight blasting them in the face all day.

Continue reading “Hackaday Links: January 10, 2021”

A Pair Of Steppers Are Put To Work In This Automatic Instrument Pickup Winder

For something that’s basically a coil of wire around some magnetic pole pieces, an electric guitar pickup is a complicated bit of tech. So much about the tone of the instrument is dictated by how the pickup is wound that controlling the winding process is something best accomplished with a machine. This automatic pickup winder isn’t exactly a high-end machine, but it’s enough for the job at hand, and has some interesting possibilities for refinements.

First off, as [The Mixed Signal] points out, his pickups aren’t intended for use on a guitar. As we’ve seen before, the musical projects he has tackled are somewhat offbeat, and this single-pole pickup is destined for another unusual instrument. That’s not to say a guitar pickup couldn’t be wound on this machine, of course, as could inductors, solenoids, or Tesla coils. The running gear is built around two NEMA-17 stepper motors, one for the coil spindle and one for the winding carriage. The carriage runs on a short Acme lead screw and linear bearings, moving back and forth to wind the coil more or less evenly. An Arduino topped with a CNC shield runs the show, allowing for walk-away coil winding.

We do notice that the coil wire seems to bunch up at the ends of the coil form. We wonder if that could be cured by speeding up the carriage motor as it nears the end of the spool to spread the wire spacing out a bit. The nice thing about builds like these is the ease with which changes can be made — at the end of the day, it’s just code.

Continue reading “A Pair Of Steppers Are Put To Work In This Automatic Instrument Pickup Winder”

Infinity Mirror Guitar Shreds Forever

Just when we thought there was nothing left to make into an infinity mirror, [Burls Art] goes and builds something that seems obvious now that it exists — an infinity mirror guitar. Check out the build video after the break, where [Burls Art] gets right to it without wasting any time.

He started by making a 3/4″ wood frame for the body and the one-piece neck and headstock. The acrylic on the top has two-way mirror film, and the back piece is painted with mirror paint to get the infinity effect going. [Burls Art] also fashioned acrylic boxes for the pickup and the electronics. Those are both buffed to be frosty, so the lights reflect nicely off of them.

There’s nothing super-fancy going on with the electronics, just some app-controlled RGB LEDs. We would love to see a version where the LEDs respond in real time to the music. The effect is still quite cool, so if you don’t want to watch the whole build, at least check out the demo at the end where [Burls Art] plays a riff. Never has a delay pedal been so appropriate.

If you’re not much of a luthier, don’t fret about not being able to make a cover version. We’ve seen plenty of infinity mirrors, but if you want something useful, whip up some infinity drink coasters.

Continue reading “Infinity Mirror Guitar Shreds Forever”

Axe Hacks: Spinning Knobs And Flipping Switches

From a guitar hacking point of view, the two major parts that are interesting to us are the pickups and the volume/tone control circuit that lets you adjust the sound while playing. Today, I’ll get into the latter part and take a close look at the components involved — potentiometers, switches, and a few other passive components — and show how they function, what alternative options we have, and how we can re-purpose them altogether.

In that sense, it’s time to heat up the soldering iron, get out the screwdriver, and take off that pick guard / open up that back cover and continue our quest for new electric guitar sounds. And if the thought of that sounds uncomfortable, skip the soldering iron and grab some alligator clips and a breadboard. It may not be the ideal environment, but it’ll work.

Continue reading “Axe Hacks: Spinning Knobs And Flipping Switches”

Raspberry Pi Crazy Guitar Rig Turns You Into A Hard ‘N Heavy One-Man Band

It’s a common problem: you’re at a party, there’s a guitar, and your plan to impress everyone with your Wonderwall playing skills is thwarted by the way too loud overall noise level. Well, [Muiota betarho] won’t have that issue ever again, and is going to steal the show anywhere he goes from now on with his Crazy Guitar Rig 2.0, an acoustic guitar turned electric — and so much more — that he shows off in three-part video series on his YouTube channel. For the impatient, here’s video 1, video 2, and video 3, but you’ll also find them embedded after the break.

To start off the series, [Muiota betarho] adds an electric guitar pickup, a set of speakers, and an amplifier board along with a battery pack into the body of a cheap acoustic guitar. He then dismantles a Zoom MS-50G multi-effect pedal and re-assembles it back into the guitar itself with a 3D-printed cover. Combining a guitar, effect pedal, amp and speaker into one standalone instrument would make this already an awesome project as it is, but this is only the beginning.

Touch screen and controls closeup
RPi touch screen running SunVox, plenty of buttons, and integrated multi-effect pedal on the left

So, time to add a Raspberry Pi running SunVox next, and throw in a touch screen to control it on the fly. SunVox itself is a free, but unfortunately not open source, cross-platform synthesizer and tracker that [Muiota betarho] uses to add drum tracks and some extra instruments and effects. He takes it even further in the final part when he hooks SunVox up to the Raspberry Pi’s GPIO pins. This allows him to automate things like switching effects on the Zoom pedal, but also provides I/O connection for external devices like a foot switch, or an entire light show to accompany his playing.

Of course, adding a magnetic pickup to an acoustic guitar, or generally electrifying acoustic instruments like a drum kit for example, isn’t new. Neither is using a single-board computer as effect pedal or as an amp in your pocket. Having it all integrated into one single device on the other hand rightfully earns this guitar its Crazy Guitar Rig name.

(Thanks for the tip, [alex]!)

Continue reading “Raspberry Pi Crazy Guitar Rig Turns You Into A Hard ‘N Heavy One-Man Band”

3D-Printed Adapter Keeps Your Guitar In Tune And In Style

If you like building or upgrading guitars, you may have already learned the valuable lesson that the devil absolutely is in the detail when it comes to to replacement parts. Maybe you became aware that there are two types of Telecaster bridges right after you drilled the holes through the body and noticed things just didn’t quite fit. Or maybe you liked the looks of those vintage locking tuners and the vibe you associate with them, only to realize later that the “vintage” part also refers to the headstock, and the holes in your modern one are too big.

The latter case recently happened to [Michael Könings], so he did what everyone with a 3D printer would: make an adapter. Sure, you can also buy them, but where’s the fun in that? Plus, the solution is as simple as it sounds. [Michael] modelled an adaptor to bridge the gap between the headstock holes and the tuner shaft, but unlike the commercial counterpart that are mounted only on one side, his fills up the entire hole and fits the entire construct tightly together. For even more overall stability, he added an interlocking mechanism on the back side that keeps all the adaptors in line, and also allows for some possible distance differences.

[Michael] initially considered using wood filament for cosmetic reasons, but due to lack of the material went with simple white PLA instead. In the end, it doesn’t matter too much, as most of it hides under the new tuners’ metal covers anyway — and the small parts that are visible will serve as a great reminder of this lesson in guitar variety. Speaking of 3D printing and guitar variety, now that we reached the headstock, and have seen bodies for a while already (including bass), only 3D-printed guitar necks are missing. Well, we’ve had them on violins though, even with 6 strings, but they also don’t have to deal with frets and have a bit less tension going on.

Axe Hacks: New Sounds For Your Electric Guitar Beginning From What Makes Them Tick

Creating music is a perfect hobby for anyone into hacking, and the amount of musical hacks and self-made instruments we come across here makes that supremely evident. It’s just a great match: you can either go full-on into engineering mode as music is in the end “just” applied physics, or simply ignore all of the theory and take an artistic approach by simply doing whatever feels right. The sweet spot is of course somewhere in between — a solid grasp of some music theory fundamentals won’t hurt, but too much overthinking eventually will.

The obvious choice to combine a favorite pastime like electronics or programming with creating music would be in the realm of electronic music, and as compelling as building synthesizers sounds, I’ll be going for the next best thing instead: the electric guitar. Despite its general popularity, the enormous potential that lies within the electric guitar is rarely fully utilized. Everyone seems to just focus on amp settings and effect pedals when looking for that special or unique sound, while the guitar itself is seen as this immutable object bestowed on us by the universe with all its predestined, magical characteristics. Toggle a pickup switch, and if we’re feeling extra perky, give that tone pot a little spin, that’s all there is to it.

The thing is, the guitar’s electrical setup — or wiring — in its stock form simply is as boring and generic as it can get. Sure, it’s a safe choice that does the job well enough, but there’s this entirely different world of tonal variety and individual controllability locked inside of it, and all it really takes is a screwdriver and soldering iron to release it. Plus, this might serve as an interesting application area to dive into simple analog electronics, so even if guitars aren’t your thing yet, maybe this will tickle your creativity bone. And if bass is more your thing, well, let me be ignorant and declare that a bass is just a longer guitar with thicker, lower-tuned strings, meaning everything that follows pretty much applies to bass as well, even if I talk about guitars.

However, in order to modify something, it helps to understand how it functions. So today, we’ll only focus on the basics of an electric guitar, i.e. what’s inside them and what defines and affects their tone. But don’t worry, once we have the fundamentals covered, we’ll be all settled to get to the juicy bits next time.

Continue reading “Axe Hacks: New Sounds For Your Electric Guitar Beginning From What Makes Them Tick”