Spy Transceiver Makes Two Tubes Do The Work Of Five

Here at Hackaday, we love following along with projects as they progress. That’s especially true when a project makes a considerable leap in terms of functionality from one version to another, or when the original design gets more elegant. And when you get both improved function and decreased complexity at the same time? That’s the good stuff.

Take the recent improvements to a vacuum tube “spy radio” as an example. Previously, [Helge (LA6NCA)] built both a two-tube transmitter and a three-tube receiver, either of which would fit in the palm of your hand. A little higher math seems to indicate that combining these two circuits into a transceiver would require five tubes, but that’s not how hams like [Helge] roll. His 80-m CW-only transceiver design uses only two tubes and a lot of tricks, which we admit we’re still wrapping our heads around. On the receive side, one tube serves as a mixer/oscillator, combining the received signal with a slightly offset crystal-controlled signal to provide the needed beat frequency. The second tube serves as the amplifier, both for the RF signal when transmitting, and for audio when receiving.

The really clever part of this build is that [Helge] somehow stuffed four separate relays into the tiny Altoids tin chassis. Three of them are used to switch between receive and transmit, while the fourth is set up as a simple electromagnetic buzzer. This provides the sidetone needed to effectively transmit Morse code, and is about the simplest way we’ve ever seen to address that need. Also impressive is how [Helge] went from a relatively expansive breadboard prototype to a much more compact final design, and how the solder was barely cooled before he managed to make a contact over 200 km. The video below has all the details.

Continue reading “Spy Transceiver Makes Two Tubes Do The Work Of Five”

Prompt Injection: An AI-Targeted Attack

For a brief window of time in the mid-2010s, a fairly common joke was to send voice commands to Alexa or other assistant devices over video. Late-night hosts and others would purposefully attempt to activate voice assistants like these en masse and get them to do ridiculous things. This isn’t quite as common of a gag anymore and was relatively harmless unless the voice assistant was set up to do something like automatically place Amazon orders, but now that much more powerful AI tools are coming online we’re seeing that joke taken to its logical conclusion: prompt-injection attacks. Continue reading “Prompt Injection: An AI-Targeted Attack”

Oscillon by Ben F. Laposky

Early Computer Art From The 1950s And 1960s

Modern day computer artist, [Amy Goodchild] surveys a history of Early Computer Art from the 1950s and 1960s. With so much attention presently focused on AI-generated artwork, we should remember that computers have been used to created art for many decades.

Our story begins in 1950 when Ben Laposky started using long exposure photography of cathode ray oscilloscopes to record moving signals generated by electronic circuits. In 1953, Gordon Pask developed the electromechanical MusiColor system. MusiColor empowered musicians to control visual elements including lights, patterns, and motorized color wheels using sound from their instruments. The musicians could interact with the system in real-time, audio-visual jam sessions.

In the early 1960s, BEFLIX (derived form Bell Flix) was developed by Ken Knowlton at Bell Labs as a programming language for generating video animations. The Graphic 1 computer featuring a light pen input device was also developed at Bell Labs. Around the same timeframe, IBM introduced novel visualization technology in the IBM 2250 graphics display for its System/360 computer. The 1967 IBM promotional film Frontiers in Computer Graphics demonstrates the capabilities of the system.

Continue reading “Early Computer Art From The 1950s And 1960s”

3D Printing Blueprints And Other Wall Art

Today if you want to reproduce a big schematic or a mechanical drawing, you just ask it to print or plot from the CAD model. But back in the day, you drew on big sheets at a drafting table. How do you make copies? Sure, there were a few large-format copiers, but they were expensive. A more common method was to use a heliographic copier which, often but not always, resulted in a blueprint — that is a blue page with white lines or vice versa. These days, you are more likely to see a blueprint as an artistic wall hanging, and since [Basement Creations] wanted some, he figured out how to make them with a 3D printer.

These prints aren’t really blueprints. They use the printer as a plotter and deposit white ink on a blue page. In the video below, he shows a number of ways to use a printer to create interesting wall art, even if you want it to be bigger than the print bed. Some of the wall art uses multiple 3D printed parts, and others use the printer as a plotter.

Continue reading “3D Printing Blueprints And Other Wall Art”

Building A Breath-Controlled MIDI Device

When we think of MIDI devices, we typically jump straight to drum machines, rack synths, and keyboard controllers. However, there’s nothing saying you can’t build your own MIDI controllers that use the magic of breath to do their musical duty. That’s precisely what [Xavier Dumont] did with this unique 3D printed build.

The device looks somewhat like an alien ship from an animated 1960s sci-fi movie, but it’s actually a sophisticated MIDI controller. Naturally, it’s peppered with buttons as every good controller should be, and it features a touch-control strip on the back.

However, the real magic is in the breath control. When the user blows into the sensor, the device sends out MIDI signals of varying intensity to control the object of the player’s desire. The breath signal can be used to modulate the mod wheel, pitch bends, or octave shifts, among a variety of other options.

[Xavier] wields the instrument with prowess in the audio demos at the end of the video. We can imagine this futuristic thing being played by a background alien in a celebration scene in a far-flung Marvel movie. Or maybe Star Wars? In any case, a triumph.

Continue reading “Building A Breath-Controlled MIDI Device”

Faster Glacier Melting Mechanism Could Cause Huge Sea Level Rises

When it comes to the issue of climate change, naysayers often contend that we have an incomplete understanding of the Earth’s systems. While humanity is yet to uncover all the secrets of the world, that doesn’t mean we can’t act on what we know. In many cases, as climate scientists delve deeper, they find yet more supporting evidence of the potential turmoil to come.

In the stark landscapes of Greenland, a team of intrepid researchers from the University of California, Irvine, and NASA’s Jet Propulsion Laboratory have unearthed a hidden facet of ice-ocean interaction. Their discovery could potentially flip our understanding of sea level rise on its head.

Continue reading “Faster Glacier Melting Mechanism Could Cause Huge Sea Level Rises”

Hackaday Podcast 219: Lots Of Lasers, Heaps Of Ham Radio, And Breaching The Blood Brain Barrier

Elliot and Dan teamed up for the podcast this week, bringing you the week’s sweetest hacks. And news too, as the ESA performed a little percussive maintenance on a Jupiter-bound space probe, and we learned about how to get an Orwellian free TV that exacts quite a price. We talked about Bitcoin mining two ways, including a way to put all that waste heat to good use — just don’t expect it to make good financial sense. Why would you stuff zip ties into a hot glue gun? It might just help with plastic repair. Lugging a tube transmitter up a mountain doesn’t sound like a good idea, but with the right design, it’s a lot of fun — and maybe you’ll be better able to tap into Schumann resonances while you’re up there.

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 a long series of ones and zeroes that, when appropriately interpreted, sound like two people talking about nerdy stuff!

Continue reading “Hackaday Podcast 219: Lots Of Lasers, Heaps Of Ham Radio, And Breaching The Blood Brain Barrier”