Hackaday Links: April 12, 2020

April 12, 2020 by Dan Maloney 14 Comments

Anyone who worked in the tech field and lived through the Y2K bug era will no doubt recall it as a time seasoned with a confusing mix of fear and optimism and tempered with a healthy dose of panic, as companies rushed to validate that systems would pass the rollover of the millennium without crashing, and to remediate systems that would. The era could well have been called “the COBOL programmers full-employment bug,” as the coders who had built these legacy systems were pulled out of retirement to fix them. Twenty years on and a different bug — the one that causes COVID-19 — is having a similarly stimulative effect on the COBOL programmer market. New Jersey is one state seeking COBOL coders, to deal with the crush of unemployment insurance claims, which are killing the 40-year-old mainframe systems the state’s programs run on. Interestingly, Governor Phil Murphy has only put out a call for volunteers, and will apparently not compensate COBOL coders for their time. I mean, I know people are bored at home and all, but good luck with that.

In another throwback to an earlier time, “The Worm” is back. NASA has decided to revive its “worm” logo, the simple block letter logo that replaced the 50s-era “Meatball” logo, the one with the red chevron bracketing a starfield with an orbiting satellite. NASA switched to the worm, named for the sinuous shape of the letters and which honestly looks like a graphic design student’s last-minute homework assignment, in the 1970s, keeping it in service through the early 1990s when the meatball was favored again. Now it looks like both logos will see service as NASA prepares to return Americans to space on their own launch vehicles.

Wait a minute, what happens when we stand this thing upright?

Looking for a little help advancing the state of your pandemic-related project? A lot of manufacturers are trying to help out as best they can, and many are offering freebies to keep you in the game. Aisler, for one, is offering free PCBs and stencils for COVID-19 prototypes. It looks like their rules are pretty liberal; any free and open-source project that can help with the pandemic in any way qualifies. Hats off to Aisler for doing their part.

And finally, history appears to have been made this week in the amateur radio world with the first direct transatlantic contact on the 70-cm band was made. It seems strange to think that it would take 120 years since transatlantic radio became reduced to practice by the likes of Marconi for this accomplishment to occur, but the 70-cm band is usually limited to line of sight, and transatlantic contacts at 430 MHz are usually done using a satellite as a relay. The contact was between stations FG8OJ on Guadaloupe Island in the Caribbean — who was involved in an earlier, similar record on the 2-meter band — and D4VHF on the Cape Verde Islands off the coast of Africa, and used the digital mode FT8. The 3,867-km contact was likely due to tropospheric ducting, where layers in the atmosphere form a refractive tunnel that can carry VHF and UHF signals much, much further than they usually go. While we’d love to see that record stretched a little more on each end, to make a truly transcontinental contact, it’s still quite an accomplishment, and we congratulate the hams involved.

Hackaday Links: April 5, 2020

April 5, 2020 by Dan Maloney 8 Comments

Git is powerful, but with great power comes the ability to really bork things up. When you find yourself looking at an inscrutable error message after an ill-advised late-night commit, it can be a maximum pucker-factor moment, and keeping a clear enough head to fix the problem can be challenging. A little proactive social engineering may be in order, which is why Jonathan Bisson wrote git-undo, a simple shell script that displays the most common un-borking commands he’s likely to need. There are other ways to prompt yourself through Git emergencies, like Oh Shit, Git (or for the scatologically sensitive, Dangit Git), but git-undo has the advantage of working without an Internet connection.

Suddenly find yourself with a bunch of time on your hands and nothing to challenge your skills? Why not try to write a program in a single Tweet? The brainchild of Dominic Pajak, the BBC Micro Bot Twitter account accepts tweets and attempts to run them as BASIC programs on a BBC Microcomputer emulator, replying with the results of the program. It would seem that 280 characters would make it difficult to do anything interesting, but check out some of the results. Most are graphic displays, some animated, and with an unsurprising number of nods to 1980s pop culture. Some are truly impressive, though, like Conway’s Game of Life written by none other than Eben Upton.

The COVID-19 pandemic is causing all sorts of cultural shifts, but we didn’t expect to see much change in the culture of a community that’s been notoriously resistant to change for over a century: amateur radio. One of the most basic facts of life in the amateur radio world is that you need a license to participate, with governments regulating the process. But as a response to the pandemic, Spain has temporarily lifted licensing requirements for amateur radio operators. Normally, an unlicensed person is only allowed to operate on amateur bands under the direct supervision of a licensed amateur. The rules change allows unlicensed operators to use a station without supervision and is intended to give schoolchildren trapped at home an educational experience. In another change, some countries are allowing special callsign suffixes, like “STAYHOME,” to raise awareness during the pandemic. And the boom in interest in amateur radio since the pandemic started is remarkable; unfortunately, finding a way to take your test in a socially distant world is quite a trick. Our friend Josh Nass (KI6NAZ) has some thoughts about testing under these conditions that you might find interesting.

And finally, life goes on during all this societal disruption, and every new life deserves to be celebrated. And when Lauren Devinck made her appearance last month, her proud parents decided to send out unique birth announcement cards with a printed circuit board feature. The board is decorative, not functional, but adds a distinctive look to the card. The process of getting the boards printed was non-trivial; it turns out that free-form script won’t pass most design rule tests, and that panelizing them required making some compromises. We think the finished product is classy, but can’t help but think that a functional board would have really made a statement. Regardless, we welcome Lauren and congratulate her proud parents.

Oscilloscope And Microscope Augmented With Ghosts

April 3, 2020 by Bryan Cockfield 13 Comments

Augmented reality saw a huge boom a few years ago, where an image of the real world has some virtual element layer displayed on top of it. To get this effect to work, however, you don’t need a suite of software and smart devices. [elad] was able to augment a microscope with the output from an oscilloscope, allowing him to see waveforms while working on small printed circuit boards with the microscope.

The build relies on a simplified version of the Pepper’s Ghost illusion. This works by separating two images with a semi-transparent material such as glass, placed at an angle. When looking through the material, the two images appear to blend together. [elad] was able to build a box that attaches to the microscope with a projection of the oscilloscope image augmented on the view of the microscope.

This looks like it would be incredibly useful for PCBs, especially when dealing with small SMD components. The project is split across two entries, the second of which is here. In one demonstration the oscilloscope image is replaced with a visual of a computer monitor, so it could be used for a lot more applications than just the oscilloscope, too. There aren’t a lot of details on the project page though, but with an understanding of Pepper’s Ghost this should be easily repeatable. If you need more examples, there are plenty of other builds that use this technique.

Continue reading “Oscilloscope And Microscope Augmented With Ghosts” →

Making PCBs With A Vinyl Cutter

April 1, 2020 by Richard Baguley 26 Comments

You might assume that you need a lot of expensive stuff to make your own PCBs, but that isn’t the case: you can do it with a vinyl cutter and a few common chemicals and tools. [Emiliano Valencia] has laid out the entire process. While we’ve seen plenty of make your own PCB guides before, this one goes a bit further as it covers using the vinyl cutter to make solder masks, so you can use it for surface mount designs.

The end result of the process that [Emilano] lays out is the tinyDice, a cute little electronic die that can fit on a keyring. The whole process is very well written up, and even experienced PCB makers will probably find a few useful tricks here.

The really interesting part for us was using the vinyl cutter to make three parts of the process: the etching mask, the solder mask that protects the traces and the solder stencil that applies the solder to the pads for surface mounting. Continue reading “Making PCBs With A Vinyl Cutter” →

Thermochromic Display Tells You The Temperature Despite Your Current Mood

March 20, 2020 by Dan Maloney 8 Comments

Readers who survived the 1970s will no doubt remember the “mood ring” fad, where a liquid crystal mounted to a ring would magically reveal your current emotional state to all and sundry by changing color. This nifty thermochromic display is based on the same principle, and while it might not start a new craze, it’s still pretty mesmerizing to watch.

This isn’t [Moritz v. Sivers]’ first attempt at a thermochromic display. His earlier version was far more complicated, using separate copper plates clad with thermochromic film for each segment, with Peltier devices to cool and heat them individually. Version two is much simpler, using a printed circuit board with heating elements in the shape of seven-segment displays etched into it. The thermochromic film sits directly on the heater PCB; a control PCB below has the MCU and sensors on it. The display alternates between temperature and humidity, with the segments fading in an uneven and ghostly way that really makes this fun to watch. [Moritz] has made the build files available, and there’s a detailed Instructable as well.

We’re always on the lookout for alternate display modalities, especially when they look this cool. We’ve seen other thermochromic displays before, of course, and persistence of phosphorescence looks great, too.

Continue reading “Thermochromic Display Tells You The Temperature Despite Your Current Mood” →

PCB Finishes Hack Chat

March 9, 2020 by Dan Maloney 3 Comments

Join us on Wednesday, March 11 at noon Pacific for the PCB Finishes Hack Chat with Mark Hughes and Elijah Gracia!

There’s no way to overestimate the degree to which the invention of the printed circuit board revolutionized electronics. What was once the work of craftspeople weaving circuits together with discrete components, terminal strips, and wiring harnesses could now be accomplished with dedicated machines, making circuit construction an almost human-free process. And it was all made possible by figuring out how to make copper foil stick to a flat board, and how to remove some of it while leaving the rest behind.

Once those traces are formed, however, there’s more work to be done. Bare copper is famously reactive stuff, and oxides soon form that will make the traces difficult to solder later. There are hundreds of different ways to prevent this, and PCB surface finishing has become almost an art form itself. Depending on the requirements for the circuit, traces can be coated with tin, lead, gold, nickel, or any combination of the above, using processes ranging from electroplating to immersion in chemical baths. And the traces aren’t the only finishes; solder resist and silkscreening are both important to the usability and durability of the finished board.

For this Hack Chat, we’ll be talking to Elijah Gracia and Mark Hughes from Royal Circuit Solutions. They’re both intimately familiar with the full range of PCB coatings and treatments, and they’ll help us make sense of the alphabet soup: HASL, OSP, ENIG, IAg, LPI, and the rest. We’ll learn what the different finishes do, which to choose under what circumstances, and perhaps even learn a bit about how to make our homebrew boards look a little more professional and perform a bit better.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 11 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

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.

3D Printing For Wire Paths Yields An Arduboy Minus The PCB

February 8, 2020 by Jenny List 23 Comments

What is part way between a printed circuit board and a rats-nest of point-to-point wiring? We’re not sure, but this is it. [Johan von Konow] has come up with an inspired solution, 3D printing an Arduboy case with channels ready-made for all the wires. The effect with his 3DPCBoy is of a PCB without the PCB, and allows the console to be made very quickly and cheaply.

The Arduboy — which we originally looked at back in 2014 — is a handheld gaming console in a somewhat Gameboy-like form factor. Normally a credit-card sized PCB hosts all the components, including a microcontroller, display, and buttons. Each has a predictable footprint and placement so they can simply be wired together with hookup wire, if you don’t mind a messy result.

Here the print itself has all the holes ready-created for the components, and the path of the wires has a resemblance to the sweeping traces of older hand-laid PCBs. The result is very effective way to take common components — and Arduino pro micro board for the uC, an OLED breakout board, and some buttons — and combine them into a robust package. This technique of using 3D prints as a combination of enclosure and substrate for components and wiring has an application far beyond handheld gaming. We look forward to seeing more like it.

[Via the Arduboy community forum, thanks Kevin Bates for the tip.]