It’s pretty easy to take a balloon, fill it up with helium, and send it up in to the upper atmosphere. It’s much harder to keep track of it and recover it when it falls back to Earth. If you’re trying to do that, you might find some value in the Tiny4FSK project from the New England Weather Balloon Society.
Tiny4FSK is intended to be a very small solution for high-altitude tracking. As you might have guessed from the name, it communicates via 4FSK—four frequency shift keying. Basically, it communicates data via four separate tones. Based around the SAMD21G18A microcontroller, it’s designed to run on a single AA battery, which should last for anywhere from 10-17 hours. It communicates via a Si4063 transmitter set up to communicate on 433.2 MHz, using the Horus Binary v2 system. As for data, it’s hooked up with a GPS module and a BME280 environmental sensor for location. The balloon can figure out where it is, and tell you the temperature, pressure, and humidity up there, too.
If you’re looking for a lightweight balloon tracker, this one might be very much up your alley. We’ve featured other projects in this vein, too. Meanwhile, if you’re developing something new in the high-altitude ballooning space, you could keep it to yourself. Or, alternatively, you could tell us via the tipsline and we’ll tell everybody else. Your call!
The build is based around the STM32L4P5—far from the hottest chip in the world. Depending on the exact part you pick, it offers 512 KB or 1 Mbyte of flash memory, 320 KB of SRAM, and runs at 120 MHz. Not bad, but not stellar.
Still, [Gabriel] was able to push 1080p at a sort of half resolution. Basically, the chip is generating a 1080p widescreen RGB VGA signal. However, to get around the limited RAM of the chip, [Gabriel] had to implement a hack—basically, every pixel is RAM rendered as 2×2 pixels to make up the full-sized display. At this stage, true 1080p looks achievable, but it’ll be a further challenge to properly fit it into memory.
Output hardware is minimal. One pin puts out the HSYNC signal, another handles VSYNC. The same pixel data is clocked out over R, G, and B signals, making all the pixels either white or black. Clocking out the data is handled by a nifty combination of the onboard DMA functionality and the OCTOSPI hardware. This enables the chip to hit the necessary data rate to generate such a high-resolution display.
Static electricity often just seems like an everyday annoyance when a wool sweater crackles as you pull it off, or when a doorknob delivers an unexpected zap. Regardless, the phenomenon is much more fascinating and complex than these simple examples suggest. In fact, static electricity is direct observable evidence of the actions of subatomic particles and the charges they carry.
While zaps from a fuzzy carpet or playground slide are funny, humanity has learned how to harness this naturally occurring force in far more deliberate and intriguing ways. In this article, we’ll dive into some of the most iconic machines that generate static electricity and explore how they work.
YouTuber The Science Furry has been attempting to make a split-anode magnetron and, after earlier failures, is having another crack at it. This also failed, but they’ve learned where to focus their efforts for the future, and it sure is fun to follow along.
The magnetron theory is simple enough, and we’ve covered this many times, but the split anode arrangement differs slightly from the microwave in your kitchen. The idea is to make a heated filament the cathode, so electrons are ejected from the hot surface by thermionic emission. These are forced into a spiral path using a perpendicular magnetic field. This is a result of the Lorentz force. A simple pair of magnets external to the tube is all that is needed for that. Depending on the diameter of the cavity and the gap width, a standing wave will be emitted. The anodes must be supplied with an alternating potential for this arrangement to work. This causes the electrons to ‘bunch up’ as they cross the gaps, producing the required RF oscillation. The split electrodes also allow an inductor to be added to tune the frequency of this standing wave. That is what makes this special.
Fizz, pop, ah well.
The construction starts with pre-made end seals with the tungsten wire electrode wire passing through. In the first video, they attempted to coat the cathode with barium nitrate, but this flaked off, ruining the tube. The second attempt replaces the coiled filament with a straight wire and uses a coating paste made from Barium Carbonate mixed with nitrocellulose in a bit of acetone. When heated, the nitrocellulose and the carbonate will decompose, hopefully leaving the barium coating intact. After inserting the electrode assembly into a section of a test tube and welding on the ends, the vacuum could be pulled and sealed off. After preheating the cathode, some gasses will be emitted into the vacuum, which is then adsorbed into a nearby titanium wire getter. At least, that’s the theory.
Upon testing, this second version burned out early on for an unknown reason, so they tried again, this time with an uncoated cathode. Measuring the emission current showed only 50 uA, which is nowhere near enough, and making the filament this hot caused it to boil off and coat the tube! They decide that perhaps this is one step too many and need to experiment with the barium coating by making simpler diode tubes to get the hang of the process!
A month ago, I’ve talked about using computers to hack on our day-to-day existence, specifically, augmenting my sense of time (or rather, lack thereof). Collecting data has been super helpful – and it’s best to automate it as much as possible. Furthermore, an augment can’t be annoying beyond the level you expect, and making it context-sensitive is important – the augment needs to understand whether it’s the right time to activate.
I want to talk about context sensitivity – it’s one of the aspects that brings us closest to the sci-fi future; currently, in some good ways and many bad ways. Your device needs to know what’s happening around it, which means that you need to give it data beyond what the augment itself is able to collect. Let me show you how you can extract fun insights from collecting data, with an example of a data source you can easily tap while on your computer, talk about implications of data collections, and why you should do it despite everything.
As we get older, our eyes get worse. That’s just a fact of life. It is a rite of passage the first time you leave the eye doctor with a script for “progressive” lenses which are just fancy bifocals. However, a new high-tech version of bifocals promises you better vision, but with a slight drawback, as [Sherri L. Smith] found.
Remember how users of Google Glass earned the nickname “glassholes?” Well, these new bifocals make Google Glass look like a fashion statement. If you are too young to need them, bifocals account for the fact that your eyes need different kinds of help when you look close up (like soldering) or far away (like at an antenna up on a roof). A true bifocal has two lenses and you quickly learn to look down at anything close up and up to see things far away. Progressives work the same, but they transition between the two settings instead of having a discrete mini lens at the bottom.
The new glasses, the ViXion01 change based on what you are looking for. They measure range and adjust accordingly. For $555, or a monthly rental, you can wear what looks like a prototype for a Star Trek visor and let it deduce what you are looking at and change its lenses accordingly.
Of course, this takes batteries that last about ten hours. It also requires medical approval to be real glasses and it doesn’t have that, yet. Honestly, if they worked well and didn’t look so dorky, the real use case might be allowing your eye doctor to immediately download a new setting as your vision changes. How about you? How much odd headgear are you willing to wear in public and why?
A word of warning before watching this very cool video on soldering: it may make you greatly desire what appears to be a very, very expensive microscope. You’ve been warned.
Granted, most people don’t really need to get this up close and personal with their soldering, but as [Robert Feranec] points out, a close look at what’s going on when the solder melts and the flux flows can be a real eye-opener. The video starts with what might be the most esoteric soldering situation — a ball-grid array (BGA) chip. It also happens to be one of the hardest techniques to assess visually, both during reflow and afterward to check the quality of your work. While the microscope [Robert] uses, a Keyence VHX-7000 series digital scope, allows the objective to swivel around and over the subject in multiple axes and keep track of where it is while doing it, it falls short of being the X-ray vision you’d need to see much beyond the outermost rows of balls. But, being able to look in at an angle is a huge benefit, one that allows us a glimpse of the reflow process.
