What’s the worst thing about traditional Morse keyers? If you ask us, it’s the fact that you have to learn how to do two distinct things with one hand, and switch between them quite quickly and often.
This set of Morse code foot pedals is meant for those who are unable to use traditional methods of keying. It uses a retrofitted wireless keyboard to read Z and X as dit and dah, respectively, and convert the Morse code into text.
[Tevendale_Engineering] started by getting the controller out of the keyboard and figuring out which combination of pads sends Z and X. Then they wired those up with copper tape. The pedals themselves are made from 1/2″-thick wood, foam core board, and Nerf bullets to provide springiness.
There’s no solder here; it’s all copper tape and alligator clip test leads. So if this isn’t your hack for the day, we don’t know what is.
Amateur Radio as a hobby has a long history of encouraging experimentation using whatever one might have on hand. When [Tom Essenpreis] wanted to use his 14 MHz antenna outside of its designed frequency range, he knew he’d need an impedance matching circuit. The most common type is an L-Match circuit which uses a variable capacitor and a variable inductor to adjust the usable frequency range (resonance) of an antenna. While inefficient in some specific configurations, they excel at bridging the gap between the 50 ohm impedance of the radio and the unknown impedance of an antenna.
It all started when [Damien Walsh] got his hands on some surplus LED boards. Each panel contained 100 mini-PCBs hosting a single bright LED that were meant to be to be snapped apart as needed. [Damien] had a much better idea: leave them in their 20×5 array and design a driver allowing each LED to be controlled over WiFi. He was successful (a brief demo video is embedded down below after the break) and had a few interesting tips to share about the process of making it from scratch.
The first hurdle he ran into was something most of us can relate to; it’s difficult to research something when one doesn’t know the correct terms. In [Damien]’s case, his searches led him to a cornucopia of LED drivers intended to be used for room lighting or backlights. These devices make a large array of smaller LEDs act like a single larger light source, but he wanted to be able to individually address each LED.
Eventually he came across the IS32FL3738 6×8 Dot Matrix LED Driver IC from ISSI which hit all the right bases. Three of these would be enough to control the 100-LED panel; it offered I2C control and even had the ability to synchronize the PWM of the LEDs across multiple chips, so there would be no mismatched flicker between LEDs on different drivers. As for micontroller and WiFi connectivity, we all have our favorites and [Damien] is a big fan of Espressif’s ESP32 series, and used the ESP32-WROOM to head it all up.
The other issue that needed attention was wiring. Each of the LEDs is on its own little PCB with handy exposed soldering pads, but soldering up 100 LEDs is the kind of job where a little planning goes a long way. [Damien] settled on a clever system of using strips of copper tape, insulated by Kapton (a super handy material with a sadly tragic history.) One tip [Damien] has for soldering to copper tape: make sure to have a fume extractor fan running because it’s a much smokier process than soldering to wires.
A 3D-printed baffle using tracing paper to diffuse the light rounds out the device, yielding a 20 x 5 matrix of individually-controlled rectangles that light up smoothly and evenly. The end result looks fantastic, and you can see it in action in the short video embedded below.
The idea of trying to prototype with SMD parts on the fly sounds like insanity, right? But then we watched [Leo Fernekes] walk calmly and carefully through his process (video, embedded below). Suddenly, SMD prototyping jumped onto our list of things to try soon.
[Leo] speaks from a lot of experience and tight client timelines, so this video is a fourteen-minute masterclass in using copper-clad board as a Manhattan-style scratch pad. He starts by making a renewable tool for scraping away copper by grinding down and shaping an old X-Acto blade into a kind of sharpened Swiss Army knife bottle opener shape. That alone is mind-blowing, but [Leo] keeps on going.
In these prototypes, he uses the through-hole version of whatever microcontroller is in the design. For everything else, he uses the exact SMT part that will end up on the PCB that someone else is busy designing in the meantime.
After laying the board out on paper, [Leo] carves out the islands of conductivity, beep-checks them for shorts, shines the whole thing with steel wool, and goes to town.
The tips and tricks keep coming as he makes jumps and joins ground planes with bare copper wire insulated with heat-proof Teflon tubing, and lays out the benefits of building up a stash of connectors and shelling out the money for a good crimp tool.
We don’t know about you, but we’re pretty tired of singing two rounds of “Happy Birthday” or counting Mississippi to 20 each time we wash our hands. It’s difficult to do it without thinking about the reason why, and that’s not good for positivity. If you’d rather have your spirits lifted every time you hit the sink, you need a better soundtrack.
Scrubber is a pretty simple build that uses a Raspberry Pi Zero W and a speaker bonnet powered by a LiPo, but we dig it just the same. The switch is adaptable to pretty much any soap dispenser — just stick two pieces of copper tape where they’ll make contact when the pump is pushed down, and solder wires to them. Check out the demo after the break.
We’ve often wondered how much more water we’re using with all the increased hand-washing out there. Adjusting to this apocalypse is arduous for all of us, but the environment is still a concern, so try to remember to turn the water off while you’re not using it. Is anyone out there working on an easy way to adapt home faucets to add motion or foot control? Because that would be awesome right about now.
What’s the worst thing about winter? If you’re as indoorsy as we are, then static electricity is probably pretty high on the list. It can ruin your chips, true, but you always wear a wrist ground strap when you handle those, right? But away from the bench, every doorknob and light switch is lying in wait, ready to shock you. If you had an anti-static ring like [LaPuge], you could be watching a tiny neon bulb light up instead of the air between your poor finger and the discharge point.
The ring itself is printed in TPU 95A filament for comfort and flexibility. There isn’t a whole lot to the circuit, just a neon bulb, a 1MΩ resistor, and some copper tape, but this piece of functional jewelry has the potential to spark up plenty of charged conversations. Zap your way past the break to see it light up against a door handle.
Hackaday editors Mike Szczys and Elliot Williams sort through the hacks you might have missed over the past seven days. In FPGA hacking news, there’s a ton of work being done on a newly discovered FPGA dev board. Kristina has a new column on input devices, kicking it off with tongue-actuated controllers. We wax philosophical about what data you need to backup and what you should let go. Plus Audacity is helping tune up CNC machines, copper tape is the prototyper’s friend, and fans of Open should take note of this laptop project.
Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!
Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!