Mysterious Files PH

It’s never been easier to get a printed circuit board made. In fact, almost every electronics video out on the internet will incessantly remind you of this fact now. But making a custom PCB wasn’t always as straightforward as sending a KiCad file to a board house. Many DIY methods involve harsh chemicals and tedious processes, but did have the potential benefit of taking much less time than waiting on boards to arrive in the mail. [Bettina Neumryr] is demonstrating one of these older methods, called the toner transfer method, using a circuit that was printed directly in an old magazine.

The first part of the toner transfer method is to create an image that can be printed. Since this circuit came from a magazine, it is first scanned in to a computer and imported into GIMP, where it can be scaled to match the size of the components and then sharpened to make a crisp print. With the image ready, it’s time to print the image onto some toner transfer paper, ensuring that the printer in question is a laser printer which actually uses toner. From there, a sheet of blank copper PCB is prepared and then the toner is transferred by heating, in this case using a laminator. After that its etched, removing all of the copper not protected by the toner, and then the toner itself can be removed which leaves behind the copper traces.

For those of you who were around when toner transfer was in vogue, this video might not have much value. But for anyone who can’t use a board manufacturer for whatever reason or is looking for alternatives, a modern video showing the method could be much more useful and have better context for beginners than videos made a decade or more ago now. Some of those older methods include similar processes using inkjet printers instead, but there are more modern DIY methods as well using lasers or CNC machines too.

The cool thing about cyberdecks is that you get to design them to suit your personal tastes. [NickZero] wanted an ultra-minimal build, and set about putting together just that.

The build is based around a Raspberry Pi Zero 2W, which has a lighter power draw than the full-fat models at the trade-off of some processing power. Since it’s a W model, it has the benefit of wireless connectivity baked in from the factory. The Pi is paired with a Gherkin 30% layout keyboard kit, which neatly matches the 7″ Waveshare touch display in width. Power is courtesy of a juicy 4000 mAh lithium-ion cell, which is taken care of by an Adafruit Powerboost 1000 charger module. Everything is then laced up together inside a nifty 3D printed case.

It’s a simple cyberdeck, and one that’s probably quite satisfying to use when you get used to the fact that there are no number or modifier keys on the ultra-cut-down keyboard. It’s also a great example of how a bunch of off-the-shelf gear can nonetheless be assembled into quite a cohesive whole. In much the opposite way, we’ve seen some maximalist cyberdeck builds lately, too.

Things are back to normal around the Podcast studio, and this week you’ll hear the dulcet tones of Elliot Williams and Kristina Panos.

In Hackaday news, we still have a Frikkin’ Lasers Challenge going on, and now you can even enter your project into it! Join the ranks, won’t you?

Not only do we have a triple mailbag this week, we have another failed attempt at guessing the sound by Kristina. However, [Baron Maximilian von Knuthausen] knew that it was a train, a British one, even. Then it’s on to the hacks, of course, which ought to go far in explaining the show title.

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!

Download in lovely MP3.

Episode 374 Show Notes:

News:

• The Frikkin Lasers Contest Starts Now (a couple weeks ago, that is).

Mailbag:

• Triple scoop! [Brett Gibson] asked whether the Hackaday Europe talks will be posted, [AT] dreams of electric tweezers, and we have an audio missive from [Shlomo Yitzchak Kaganoff], who wants to know what the most elaborate and/or interesting home automation is that exists. Can you weigh in? Of course you can. Will you?
• Found Footage: Elliot Williams Talks Nexus Technologies

Interesting Hacks of the Week:

• Behold A 60 Hz Refresh Rate E-ink Monitor
  • Supercon 2024: Wenting Zhang – Making E-Ink Go Fast – YouTube
• Commodore Unveils Linux Powered Flip Phone
• OpenCAL: Computed Axial Lithographic 3D Printing For Everyone
  • CAL 3D Printing Spins Resin Right Round, Baby
  • Prints in Seconds – NOW OPEN SOURCE! Computed Axial Lithography! – YouTube
• Wooden Piano Keys Hold Your Less-Wooden, Not-Piano Keys
• Building A Ceiling-Based Crane Robot To Keep A Room Clean
  • lerobot (LeRobot)
  • Cable Bots, Arise! Domination Of The Universe Is At Hand
• Ergonomic Mouse Gives Each Fingertip Its Own Saddle

Quick Hacks:

• Elliot’s Picks:
  • 2026 Frikkin Lasers Contest: Glow Engine Is Like An Open Air Slow Scan CRT
  • 2026 Frikkin Lasers Contest: Steampunk, 360 O-Scope Does It With Tubes
  • The Pacemaker Patch
  • IKEA Storage Box Just Happens To Make Great Printer Cover
• Kristina’s Picks:
  • 3D Printed Hose Sprayer Sets Phasers To Suds
  • Adding Weight To A 3D Print With Plaster Of Paris, Cleanly
  • Homebrew Macropad Looks Good

Can’t-Miss Articles:

• What Happens If Russia Shuts The Door On Their Leaky ISS Module?
• How Did They Make View-Master Slides?
  • Inexpensive Reading Glasses Become Stereoscope

We feature a lot of fun projects with LEDs and lasers and all kinds of light effects going on. Most of these are very digital. However, there are a great many ways to make beautiful lighting effects without ones and zeros. The Maelstrom Lamp from [Michele Lorenzi] is a great example of that.

The concept is decidedly old-school. The lamp uses a delicate, thin soap film stretched across an aperture as its primary optical element. The varying thickness of the film across its surface leads to constructive and destructive interference when white light passes through it. This creates a kaleidoscope of color; the same effect you might have seen when an oil slick forms in a dirty puddle.

In this case, though, that effect is projected with the aid of a powerful 800-lumen flashlight and some supporting optics. [Michele]’s write-up does a great job of explaining the finer design details that maximize the vibrancy of the effect, from the waviness in the gasket that supports the soap film, to the optics that focus the torch beam.

If you’re looking for some suitably psychedelic lighting effects for your next house party, you really ought to build one of these. We’ve featured some other fun classic lighting effects before, like these wonderful bubble lamps.

There are a million and one cheap OLED display modules out there. Only, the problem is, they’re all assembled on bare PCBs and they’re all slightly different, and that frustrates efforts to mount them in a clean and tidy manner. [Galopago] decided to build a small OLED module that solved this frustrating problem.

The idea to pursue this came from off-the-shelf panel displays commonly used for power supply builds and other such equipment. These come in relatively standard sizes and are designed from the outset to slot neatly into a panel with a bezel that covers any ugly edges or awkward gaps.

The build began with a 48 x 29mm enclosure grabbed from an off-the-shelf power panel meter. There are two PCBs—one holding the regulator and other equipment to run the display, the other carrying a set of screw terminals that make it easy to wire up the display to a piece of equipment. The SSD1306-copmatible OLED screen itself connects to the first board with a flat flex cable, as is the norm.

If you find yourself often wanting to pop a small display into a piece of custom test equipment, this might be relevant to your interests. Files are on Github for the curious.

We’ve featured some other fun OLED hacks over the years, like this interesting effort to whip up displays from scratch in a home lab. If you’ve got nifty usability hacks of your own in the works, don’t hesitate to let us know.

Do you have a ZKETECH EBC-A20 battery tester? Perhaps you don’t like the default software used to control the device. In that case, you might like the alternative whipped up by [Kazhuu.]

A reverse-engineering effort targeted at the EBC-A20 served as the basis for the work. The battery tester is ultimately controlled by a simple serial interface, running at 9600 bps, 8 bits, with odd parity. Armed with a relatively complete understanding of the commands used to control the device, [Kazhuu] was able to whip up a simple web app to control the device instead, using WebUSB to access the device over a USB-to-serial converter, though a desktop version for Linux and Windows is also available. If you’ve got one of these battery testers sitting on your bench, using the app is as simple as pointing your browser here with the device plugged in via USB. Then you can run basic load tests on battery cells and graph the results right on your computer without having to deal with the proprietary software.

Of course, if you don’t like the EBC-A20 battery tester, you could always build your own. If you’re whipping up your own test hardware on the lab bench, don’t hesitate to notify us on the tipsline.

Holographic displays sound very fancy but you can build various simple types yourself at home. [Julius Makes] whipped up a neat design that shows a different image depending on the position from which you view it. 

Running the show is a Wemos D1 devboard equipped with the ESP8266 microcontroller. It’s hooked up to a pair of OLED displays over I2C. The displays are placed in a 3D printed assembly that aims each one at a beam-splitter cube. This bounces light projected into one face through 90 degrees, and out another face. By leveraging this, it’s possible to aim each display at one face and bounce it out another, such that looking at either side of the beamsplitter cube shows a different image. Since the beamsplitter cube also allows some light to be transmitted directly through as well, the image from each display appears to float in space.

[Julius] notes that this setup is being used in a puzzle box game, while wondering whether there’s any other fun ways to leverage this technique. We’ve seen some other neat holographic displays before, too, like this neat Holochess build.