Do you sometimes feel that your custom mechanical keyboard is not quite loud enough to proclaim your superior hacking powers? Or do you need a more forceful way shout in all caps at someone who is wrong on the internet? For all this and more, [Jesse Li] has got you covered, with a set of bash scripts that allows you to type by slamming your laptop closed repeatedly, using Morse code.
The scripts are quite simple, and work receiving the lid open/close events from ACPI (Advanced Configuration and Power Interface), recording the open and close timestamp and converting the timing to dots and dashes. After slamming to the required rhythm, you keep the lid open to see the character appear.
Why would want this? Well, you can now type the letter E by closing your laptop, instead of locking it. Maybe use it to send an emergency message while you’re being held by terrorists in a B-grade action movie. Otherwise, we think this is just an entertaining little hack that’s probably the product of quarantine induced boredom.
Morse code, otherwise known as CW, is still in surprisingly widespread use by ham radio operators, because it’s good at getting messages across intercontinental distances when signal conditions are bad and CW-only ham radio gear is cheap and easy to build yourself. We’ve also covered the Koch Method of learning CW, so don’t be afraid to dabble a bit during the quarantine.
For many hams, the most enticing part of amateur radio is homebrewing. There’s a certain cachet to holding a license that not only allows you to use the public airwaves, but to construct the means of doing so yourself. Homebrew radios range from simple designs with a few transistors and a couple of hand-wound coils to full-blown rigs that rival commercial transceivers in the capabilities and build quality — and sometimes even surpass them. Hams cook up every piece of gear from the antenna back, and in many ways, the homebrewers drive amateur radio technology and press the state of the art forward.
Taking the dive into homebrewing can be daunting, though. The mysteries of the RF world can be a barrier to entry, and having some guidance from someone who has “been there, done that” can be key to breaking through. New Zealand ham Charlie Morris (ZL2CTM) has been acting as one such guide for the adventurous homebrewer with his YouTube channel, where he presents his radio projects in clear, concise steps. He takes viewers through each step of his builds, detailing each module’s design and carefully walking through the selection of each component. He’s quick to say that his videos aren’t tutorials, but they do teach a lot about the homebrewer’s art, and you’ll come away from each with a new tip or trick that’s worth trying out in your homebrew designs.
Charlie will join us for the Hack Chat this Wednesday to discuss all things homebrewing. Stop by with your burning questions on DIY amateur radio, ask about some of Charlie’s previous projects, and get a glimpse of where he’s going next.
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Most countries have dropped the requirement for learning Morse code to become a ham radio operator. Because of that, you might think Morse code is dead. But it isn’t. Some people like the nostalgia. Some like that you can build simple equipment to send and receive Morse code. Others like that Morse code is much more reliable than voice and some older digital modes. Regardless of the reason, many people want to learn Morse code and it is still a part of the ham radio scene. The code has a reputation of being hard to learn, but it turns out that is mostly because people haven’t been taught code in smart ways.
I don’t know if they still do, but some youth organizations used to promote some particularly bad ways to learn the code. The second worse way is to learn “dots and dashes” and many people did learn that way. The very worst way was using an image like the adjacent one to try to map the dots and dashes into letter shapes. This chart dates back to at least 1918 when a Girl Guides handbook printed it.
Even if you are a visual learner, this is a bad idea. The problem is, it is nearly impossible to hear sounds at 20 or 30 words per minute and map them to this visual representation. Another visual method is to use a binary tree where left branches are dots and right branches are dashes.
If you only need to master 5 words per minute to get a merit badge, you might get away with this. But for real use, 5 words a minute is very slow. For example, this sentence would take about 3 minutes to send at that speed. Just that one sentence.
Conventional wisdom holds that the best way to learn a new language is immersion: just throw someone into a situation where they have no choice, and they’ll learn by context. Militaries use immersion language instruction, as do diplomats and journalists, and apparently computers can now use it to teach themselves Morse code.
The blog entry by the delightfully callsigned [Mauri Niininen (AG1LE)] reads like a scientific paper, with good reason: [Mauri] really seems to know a thing or two about machine learning. His method uses curated training data to build a model, namely Morse snippets and their translations, as is the usual approach with such systems. But things take an unexpected turn right from the start, as [Mauri] uses a Tensorflow handwriting recognition implementation to train his model.
Using a few lines of Python, he converts short, known snippets of Morse to a grayscale image that looks a little like a barcode, with the light areas being the dits and dahs and the dark bars being silence. The first training run only resulted in about 36% accuracy, but a subsequent run with shorter snippets ended up being 99.5% accurate. The model was also able to pull Morse out of a signal with -6 dB signal-to-noise ratio, even though it had been trained with a much cleaner signal.
Other Morse decoders use lookup tables to convert sound to text, but it’s important to note that this one doesn’t. By comparing patterns to labels in the training data, it inferred what the characters mean, and essentially taught itself Morse code in about an hour. We find that fascinating, and wonder what other applications this would be good for.
You might have to provide your own wrist straps and eye clamps, but if you want to learn Morse code, [Seth] has a web site for you. You can get code practice using the Farnsworth method and each letter is flashed before you as it is sent, which we assume will burn it into your brain.
Why learn Morse code now? Just about all countries now have at least some no code ham licenses and many have taken code off the tests completely. However, there are still many hams that use the code even today. Why? The personal challenge is part of it and perhaps nostalgia. However, it is also true that Morse code transmitters and receivers are dead simple to build and can get through where other simple radios can’t.
[W8BH] attended a talk by another ham, [W8TEE] that showed a microcontroller sending and receiving Morse code. He decided to build his own, and documented his results in an 8 part tutorial. He’s using the Blue Pill board and the resulting device sends code with paddles, sends canned text, provides an LCD with a rotary knob menu interface, and even has an SD card for data storage.
All the code is on GitHub. If you are interested in Morse code or in learning how to write a pretty substantial application using the Blue Pill and the Arduino IDE (or any other similar processor), this is a great exposition that is also a practical tool.
Many of us have fond memories of our introduction to electronics through the “200-in-1” sets that Radio Shack once sold, or even the more recent “Snap Circuits”-style kits. Most of eventually us move beyond these kits to design our circuits; still, there’s something to be said for modular designs. This complete amateur radio transceiver is a great example of that kind of plug and play construction.
The rig is the brainchild of [jmhrvy1947], who set out to build a complete transceiver using mostly eBay-sourced modules. Some custom PCBs are used, but those are simple boards that can be etched and drilled easily. The transceiver is only for continuous-wave (CW) use, which would normally mean you’d need to know Morse, but thanks to some clever modifications to open-source apps like Quisk and FLDigi, Morse can be received and sent directly from the desktop. That will no doubt raise some hackles, but we think it’s a great way to learn code. The rig is QRP, or low power, transmitting only 100 mW with the small power amp shown. Adding eBay modules can jack that up to a full 100 Watts, which also requires adding a 12-volt power supply, switchable low-pass filters, a buck-boost converter, and some bandpass filters for band selection. It ends up looking very experimental, but it works well enough to make contacts.
We really like the approach here, and the fact that the rig can be built in stages. That makes it a perfect project for our $50 Ham series, which just kicked off. Perhaps we’ll be seeing it again soon.