With the assistance of an extra pair of hands, but without any power tools in sight, this old master marks up a piece of wood and then cuts a collapsible chair out of it. He uses various types of saw, chisels, a manual drill, and various other hand tools. His workspace is a humble plank with a large clamp attached. At the end he does use a powered hot air gun to heat the finish he uses to coat the final product.
At first glance, [RobBest]’s constant current source looks old school. The box is somewhat old-fashioned, featuring switches and binding posts. Most importantly, there’s a large analog meter dominating the front panel. Then you notice the OLED display, and you know something’s up.
The device can source or sink a constant current. In addition, it features a timer that calculates milliamp-hours and automatically turns off when not in use. The brain is a PIC 16F1765, which controls the screen, the buttons, and a few relays. While that might seem an odd choice for the processor, it is actually smart. The device has both a DAC and an ADC, plus an internal op amp. The analog output and a single pass transistor control the current flow, while the two relays flip it between a source and a sink.
Without that op amp, the DAC can’t produce much current. However, by passing it through the onboard amplifier, the output can drive about 100 mA, which is sufficient for this project.
This is a classic circuit, but the addition of a CPU and a display gives it capabilities that would have been very difficult to build back in the day. Want to dive into the theory behind constant current sources? Or just the practical use of a voltage regulator to make one?
When you think of neon, you might think of neon signs or the tenth element, a noble gas. But there was a time when neon bulbs like the venerable NE-2 were the 555 of their day, with a seemingly endless number of clever circuits. What made this little device so versatile? And why do we see so few of them today?
Neon’s brilliant glow was noted when William Ramsay and Morris Travers discovered it in 1898. It would be 1910 before a practical lighting device using neon appeared. It was 1915 when the developer, Georges Claude, of Air Liquide fame, received a patent on the unique electrodes suitable for lighting and, thus, had a monopoly on the technology he sold through his company Claude Neon Lights.
However, Daniel Moore in 1917 developed a different kind of neon bulb while working for General Electric. These bulbs used coronal discharge to produce a red glow or, with argon, a blue glow. This was different enough to earn another patent, and neon bulbs found use primarily as indicator lamps before the advent of the LED. However, it would also find many other uses.
Entries keep ticking in for the One Hertz Challenge, some more practical than others. [Pierre-Loup M.]’s One Hertz Sculpture has no pretensions of being anything but pretty, but we can absolutely respect the artistic impulse behind it.
The sculpture is a free-form circuit inside of a picture frame. There are 9 LEDs in a ring with a few other components to produce a reverse-chase effect (one going dark at a time) taking about 1 second to circle the sculpture. As far as free-form circuit art goes, it’s handsomely done, but as this is Hackaday it’s probably the electronics, rather that the aesthetics that are of interest.
The circuit is an example of a ring oscillator: a cascading chain of NOT gates, endlessly feeding into and inverting one
Without timing it, it looks like 1 Hz, even if we know it’s not.
another. The NOT gates are implemented in resistor-transistor logic with 2N3904 NPN transistors, nine in total. Of course the inverter delay of this sort of handmade logic gate is far too fast for an aesthetically pleasing (or visible) chase, so some extra circuitry is needed to slow down the oscillations to something less than the 5 MHz it would naturally do. This is affected by pairing every transistor with an RC oscillator. Ideally the RC oscillator would have a 0.111..s period (1/9th of a second), but a few things got in the way of that. The RC oscillator isn’t oscillating in a vacuum, and interactions with the rest of the circuit have it running just a little bit fast. That’s really of no matter; a simple oscillator circuit like this wasn’t going to be a shoe in for the accuracy-based Time Lords category of this contest. As a sculpture and not a clock, you’re not going to notice it isn’t running at exactly 1Hz. (Though a ring-oscillator based clock would be a sight indeed.)
PC gaming in the modern era has become a GPU measuring contest, but back when computers had far fewer resources, every sprite had to be accounted for. To many, this was peak gaming. So let’s look to the greats of [Martin Hollis, David Moore, and Olly Betts], who had the genius (or insanity) to create Tetris in a single BBC BASIC line.
Created in 1992, one-line Tetris serves as a great use of the limited resources available. The entirety of the game fits within 257 bytes. With the age of BASIC, the original intent of the game for BBC BASIC was to be played on computers similar to Acorn’s BBC microcomputer or Archimedes.
One line Tetris has all the core features of the original game. Moving left, right, and rotating all function like the traditional game, most of the time. Being created in a single line, there were a few corners cut with bug fixing. Bugs such as crashing every 136 years of play due to large numbers or holding all keys causing the tetrominoes to freeze make it an interesting play experience. However, as long as our GPUs are long enough to play, we don’t mind.
If you want to experience the most densely coded gaming experience possible but don’t have one of the BBC BASIC computers of old, make sure to try this emulator with a copy of the game. Considering the amount done in a single line of BBC BASIC, the thought may come into mind on what could be done with MORE than a SINGLE line of code. For those with this thought, check out the capabilities of the coding language with modern hardware.
It’s hard to argue that Soviet-Era nuclear engineering may have some small flaws, what with the heavily-monitored exclusion zone around Chernobyl No.4. Evidently, their industrial designers were more on-the-ball, because [Alex] has crafted the absolute most stylish fallout monitor we’ve ever seen, with ESP32 and a vintage Soviet-designed plasma display to indicate radiation levels in the exclusion zone.
Since the device is not located within the zone, [Alex] is using the ESP32 to access sensor values published via an API at SaveEcoBot. He also includes a Geiger counter module for the background level at the current location. That’s straightforward enough– integrating the modern microcontroller with the vintage plasma display is where the real hacking comes in. Though they might not be as vintage as you think: apparently the Elektronika MS6205 remained in production until 2005, but 2005 is still vintage. [Alex] notes in the instructions on hackaday.io that we’re actually looking for a post-1995 model to follow along.
The Elektronika MS6205 is based on a 100×100 pixel plasma matrix, but it is operated as a text-only display with Latin and Cyrillic characters in ROM. The ROM also includes some extra symbols and Greek letters (the gamma will come in handy for this application) that can be unlocked by cutting a trace on the board and replacing it with a bodge wire. Igniting the display requires 250V, which will require more work for North Americans than it does in Ukraine. Driving the display requires interfacing with the 7-bit data bus and 8-bit address bus, but [Alex] has made the wiring and code available on the project site if you’re interested in these devices. If you want to watch it in action and get more background, check out the video embedded below.
Zines (self-produced, small-circulation publications) are extremely DIY, and therefore punk- and hacker-adjacent by nature. While they can be made with nothing more than a home printer or photocopier, some might benefit from professional production while losing none of their core appeal. However, the professional print world has a few gotchas, and in true hacker spirit [Mabel Wynne] shares things she learned the hard way when printing her solo art zine.
As with assembling hardware kits, assembling a zine can take up a lot of physical table space.
[Mabel] says the most useful detail to nail down before even speaking to printers is the zine’s binding, because binding type can impact layout and design of an entire document. Her advice? Nail it down early, whether it’s a simple saddlestitch (staples through a v-shaped fold of sheets), spiral binding (which allows a document to lay flat), or something else.
Aside from paper and print method (which may be more or less important depending on the zine’s content) the other thing that’s important to consider is the finishing. Finishing consists of things like cutting, folding, and binding of the raw printed sheets. A printer will help arrange these, but it’s possible to do some or even all of these steps for oneself, which is not only more hands-on but reduces costs.
Do test runs, and prototype the end result in order to force unknown problems to the surface before they become design issues. Really, the fundamentals have a lot in common with designing and building kits or hardware. Check out [Mabel]’s article for the full details; she even talks a little about managing money and getting a zine onto shelves.
Zine making is the DIYer’s way to give ideas physical form and put them into peoples’ hands more or less directly, and there’s something wonderfully and inherently subversive about that concept. 2600 has its roots in print, but oddball disk magazines prove one doesn’t need paper to make a zine.
