Hacker Tools, Hacked Tools

December 14, 2024 by Elliot Williams 3 Comments

We just love a good DIY tool project, and more so when it’s something that we can actually use cobbled together from stuff in our closet, or hacked out of cheap “toys”. This week we saw both a superb Pi Pico-based logic analyzer and yet another software frontend for the RTL-SDR dongle, and they both had us thinking of how good we have it.

If you don’t already have a logic analyzer, or if you have one of those super-cheap 8-channel jobbies, it might be worth your while to check out the Pico firmware simply because it gets you 24 channels, which is more than you’ll ever need™. At the low price of $4, maybe a little more if you need to add level shifters to the circuit to allow for 5 V inputs, you could do a lot worse for less than the price of a fancy sweet coffee beverage.

And the RTL dongle; don’t get us started on this marvel of radio hacking. If you vaguely have interest in RF, it’s the most amazing bargain, and ever-improving software just keeps adding functionality. The post above adds HTML5 support for the RTL-SDR, allowing you to drive it with code you host on a web page, which makes the entire experience not only cheap, but painless. Talk about a gateway drug! If you don’t have an RTL-SDR, just go out and buy one. Trust me.

What both of these hacker tools have in common, of course, is good support by a bunch of free and open software that makes them do what they do. This software enables a very simple piece of hardware to carry out what used to be high-end lab equipment functions, for almost nothing. This has an amazing democratizing effect, and paves the way for the next generation of projects and hackers. I can’t think of a better way to spend $20.

Tis The Season

December 7, 2024 by Elliot Williams 16 Comments

’Tis the season for soldering! At least at my house. My son and I made some fairly LED-laden gifts for the immediate relatives last year, and he’s got the blinky bug. We were brainstorming what we could make this year, and his response was “I don’t care, but it needs to have lots of LEDs”.

It’s also the season for reverse engineering, apparently, because we’re using a string of WS2812-alike “fairy lights”. These are actually really neat, they look good and are relatively cheap. It’s a string of RGB LEDs with drivers, each dipped in epoxy, and run on a common three-enameled-wire bus. Unlike WS2812s, which pass the data on to the next unit in the line and then display them with a latching pulse at the end of a sequence, these LED drivers seem to count how many RGB packets have been sent down the wire, and only respond to their own number.

This means that if you cut up a string of 200 LEDs, it behaves like a string of 200 WS2812s. But if you cut say 10 LEDs off the string, where you cut them matters. If you cut it off the front of the string, you only have to send 10 color packets. If you cut them off the other end, you need to send 290 dummy packets before they even start listening. Bizarre, but ’tis the season for bizarre hacks.

And finally, ’tis the season for first steps into “software architecture”. Which is to say that my son is appreciating functions for the first time in his life. Controlling one LED is easy, but making a light show is about two more abstraction layers on top of that. We’ve been having fun making them dim, twinkle, and chase so far. We only have two more weekends, though, and we don’t have a final light show figured out yet, but after all, ’tis the season for last minute present hacking.

A light grey background with white and black line drawings of three different bicycles on one page and three different tire levers and three different valve covers for bikes on the other.

A Beautifully Illustrated Guide To Making

November 10, 2024 by Navarre Bartz 13 Comments

If you’ve ever been wondering what you should make next, it can be a daunting task to decide with the firehose of inspiration coming straight from the series of tubes that makeup the World Wide Web. Perhaps a more curated digital catalog of projects would help?

Featuring “1000 Useful Things to Make,” [NODE]’s Make it Yourself is a beautifully-illustrated catalog of open source and DIY projects spanning a number of domains including camping gear, furniture, music, and maker tools. Each image is a link to the original project and there’s a handy icon by each denoting what skills are needed, such as sewing or 3D printing.

If you haven’t seen [NODE]’s work before, he uses line art to illustrate his projects and has given all of these projects the same treatment on the (virtual) page with credits to the original creators in the footnotes. We hope a future edition will include tractors and houses to truly rival the Sears catalog of yore, but it’s hard to complain when we already have so many projects we could choose to build.

Many of the projects may seem familiar, if slightly fancier when illustrated in line art, like the Ploopy headphones, this retro audio player, or the Keybon adaptive macro pad.

Continue reading “A Beautifully Illustrated Guide To Making” →

DIY Core Rope Memory Z80 Demonstrator Generating A Fibonacci Sequence

October 16, 2024 by Dave Rowntree 14 Comments

We’ve seen a few retro products using core rope memory, such as telephone autodiallers. Obviously, we’ve covered the Apollo program computers, but we don’t think we’ve seen a complete and functional DIY computer using core rope memory for program storage until now. [P-lab] presents their take on the technology using it to store the program for a Z80-based microprocessor demoboard, built entirely through-hole on a large chunk of veroboard.

For the uninitiated, core rope memory is a simple form of ROM where each core represents a bit in the data word. Each wire represents a single program location. Passing a wire through the core sets the corresponding bit to a logic 1, else 0. These wires are excited with an AC waveform, which is coupled to the cores that host a wire, passing along the signal to a pickup coil. This forms an array of rudimentary transformers. All that is needed is a rectifier/detector to create a stable logic signal to feed onto the data bus.

Continue reading “DIY Core Rope Memory Z80 Demonstrator Generating A Fibonacci Sequence” →

Where Is The End Of DIY?

October 5, 2024 by Elliot Williams 70 Comments

Al and I were talking on the podcast about Dan Maloney’s recent piece on how lead and silver are refined and about the possibility of anyone fully understanding a modern cellphone. This lead to Al wondering at the complexity of the constructed world in which we live: If you think hard enough about anything around you right now, you’d probably be able to recreate about 0% of it again from first principles.

Smelting lead and building a cellphone are two sides of coin, in my mind. The process of getting lead out of galena is simple enough to comprehend, but it’s messy and dangerous in practice. Cellphones, on the other hand, are so monumentally complex that I’d wager that no single person could even describe all of the parts in sufficient detail to reproduce them. That’s why they’re made by companies with hundreds of engineers and decades of experience with the tech – the only way to build a cellphone is to split the complicated task into many subsystems.

Smelting lead is a bad DIY project because it’s simple in principle, but prohibitive in practice. Building a cellphone from the ground up is incomprehensible in principle, but ironically entirely doable in practice if you’re willing to buy into some abstractions.

Indeed, last week we saw a nearly completely open-source build of a simple smartphone, and the secret to making it work is knowing the limits of DIY. The cell modem, for instance, is a black box. It’s an abstract device that you can feed data to and read data from, and it handles the radio parts of the phone that would take forever to design from scratch. But you don’t need to understand its inner workings to use it. Knowing where the limits of DIY are in your project, where you’re willing to accept the abstraction and move on, can be critical to getting it done.

Of course, in an ideal world, you’d want the cell modem to be like smelting lead – something that’s possible to understand in principle but just not worth DIYing in practice. And of course, there are some folks out there who hack on cell modem firmware and others who could do the radio engineering. But despite my strong DIY urges, I’d have to admit that the essential complexity of the module simply makes it worth treating as a black box. It’s very probably the practical limit of DIY.

Building A 3D Printed Scanning Tunneling Microscope

September 30, 2024 by Dave Rowntree 12 Comments

YouTuber [MechnicalRedPanda] has recreated a DIY STM hack we covered about ten years ago, updating it to be primarily 3D-printed, using modern electronics, making it much more accessible to many folks. This simple STM setup utilises a piezoelectric actuator constructed by deliberately cutting a piezo speaker into four quadrants. With individual drive wires attached to the four quadrants. [MechPanda] (re)discovered that piezoelectric ceramic materials are not big fans of soldering heat. Still, in the absence of ultrasonic welding equipment, he did manage to get some wires to take to the surface using low-temperature solder paste.

As you can tell, you can only image conductive samples

A makeshift probe holder was glued on the rear side of the speaker actuator, which was intended to take a super sharp needle-like piece of tungsten wire. Putting the wire in tension and cutting at a sharp angle makes it possible with many attempts to get some usable points. Usable, in this instance, means sharp down the atomic level. The sample platform, actuator mount and all the connecting parts are 3D-printed with PA-CF. This is necessary to achieve enough mechanical stability with normal room temperature fluctuations. Three precision screws are used to level the two platforms in a typical kinematic mount structure, which looks like the only hard-to-source component. A geared stepper motor attached to the probe platform is set up to allow the probe to be carefully advanced towards the sample surface. Continue reading “Building A 3D Printed Scanning Tunneling Microscope” →

Shoot Smooth Video From Your Phone With The Syringe Slider

September 29, 2024 by Donald Papp 5 Comments

We love the idea [Btoretsukuru] shared that uses a simple setup called the Syringe Slider to take smoothly-tracked video footage of small scenes like model trains in action. The post is in Japanese, but the video is very much “show, don’t tell” and it’s perfectly clear how it all works. The results look fantastic!

The device consists of a frame that forms a sort of enclosed track in which one’s mobile phone can slide horizontally. The phone butts up against the plunger of an ordinary syringe built into the frame. As the phone is pushed along, it depresses the plunger which puts up enough resistance to turn the phone’s slide into a slow, even, and smooth glide. Want to fine-tune the resistance and therefore the performance? Simply attach different diameter tips to the syringe.

The results speak for themselves, and it’s a fantastically clever bit of work. There are plenty of DIY slider designs (some of which get amazingly complex) but they are rarely small things that can be easily gotten up close and personal with small subjects like mini train terrain.

Continue reading “Shoot Smooth Video From Your Phone With The Syringe Slider” →