Congratulations, you have just finished assembling your electronics project. After checking for obvious problems you apply power and… it didn’t do what you wanted. They almost never work on the first try, and thus we step into the world of electronics debugging with Daniel Samarin as our guide at Hackaday Superconference 2019. The newly published talk video embedded below.
Beginners venturing just beyond blinking LEDs and premade kits would benefit the most from information here, but there are tidbits useful for more experienced veterans as well. The emphasis is on understanding what is actually happening inside the circuit, which explains the title of the talk: Debugging Electronics: You Can’t Handle the Ground Truth! So we can compare observed behavior against designed intent. Without an accurate understanding, any attempted fix is doomed to failure.
To be come really good at this, you need to embrace the tools that are often found on a well stocked electronics bench. Daniel dives into the tricks of the trade that transcend printf and blinking LED to form a plan to approach any debugging task.
Stop me if this sounds familiar. You are interested in 3D printing but lacked a clear idea of what was involved. Every time you looked into it, it returned to the back burner because after spending your limited free time researching, it still looked like a part time job just to get up to speed on the basics. If this is you, then you’re exactly the reason I say the following: despite 3D printing being more accessible than ever, getting started remains harder than it needs to be. It’s a shame, because there are smart, but busy, people just waiting for that to change.
A highly technical friend and colleague of mine had, off and on, been interested in 3D printing for some time. He had questions, but also didn’t have a very good understanding of the basics because it’s clumsy and time-consuming to research something when one doesn’t even know the right terms.
I told him to video call me. Using my phone I showed him the everyday process, from downloading a model to watching the first layer get put down by the printer. He had researched getting started before, but our call was honestly the first time he had ever seen a 3D printer’s actual workflow, showing hands-on what was involved from beginning to end. It took less than twenty minutes to give him a context into which he could fit everything else, and from where he felt comfortable seeking more information. I found out later, when I politely inquired whether he had found our talk useful, that he had ordered a Prusa MK3S printer later that same day.
It got me thinking. What from our call was important and useful, but not available elsewhere? And why not?
In the world of business cards, it seems that for some people a white rectangle of card just doesn’t cut it any more. A card isn’t simply a means to display your contact details, instead it can be a way to show off your work and demonstrate to the world your capabilities. For [agepbiz] those are the skills of a 3D design specialist, so what better way to proceed than by distributing a 3D-printed example of his work? How to render that into a business card? Put it in a retail-style blister pack, of course. Take a look at the video below the break.
It’s an interesting process to follow, because there are certainly readers who will have toyed with the idea of selling their work, and this makes an attractive way to display a small assembly while still keeping it safe from damage. The toy – a small 3D-printed jet fighter with working swing wings that’s a masterpiece in itself – is laid on a backing card and a custom blister is glued over it. The manufacture of the printed backing card with a CNC card cutter is shown, followed by that of the blister with a custom SLA-printed mould being used to vacuum-form a sheet of clear plastic. Surprisingly the whole is assembled with just a glue stick, we’d have expected something with a bit more grab. The result is a professional-looking blister packed product of the type you wouldn’t bat an eyelid over if you saw it in a shop, and one of those things that it’s very useful to have some insight into how one might be made..
It’s possible this card might be a little bulky to slip in your wallet, but it’s hardly the only novelty card we’ve brought you over the years. Some of our most recent favourites run Linux or play Tetris.
From the Age of Sail through to the Second World War, naval combat was done primarily in close quarters and with cannons. Naturally the technology improved quite a bit in those intervening centuries, but the idea was more or less the same: the ship with the most guns and most armor was usually the one that emerged victorious. Over the years warships became larger and heavier, a trend that culminated in the 1940s with the massive Bismarck, Iowa, and Yamato class battleships.
But by the close of WWII, the nature of naval combat had begun to change. Airplanes and submarines, vastly improved over their WWI counterparts, presented threats from above and below. A few years later, the advent of practical long-range guided missiles meant that adversaries no longer had to be within visual range to launch their attack. Going into the Cold War it became clear that to remain relevant, warships of the future would need to be smaller, faster, and smarter.
The aft flight deck of a modular LCS
It was this line of thinking that lead the US Navy to embark on the Littoral Combat Ship (LCS) program in the early 2000s. These ships would be more nimble than older warships, able to quickly dash through shallow coastal waters where adversaries couldn’t follow. Their primary armament would consist of guided missiles, with fast firing small-caliber guns being relegated to defensive duty. But most importantly, the core goal of the LCS program was to produce a modular warship.
Rather than being built for a single task, the LCS would be able to perform multiple roles thanks to so-called “mission modules” which could be quickly swapped out as needed. Instead of having to return to home port for a lengthy refit, an LCS could be reconfigured for various tasks at a commercial port closer to the combat area in a matter of hours.
A fleet of ships that could be switched between combat roles based on demand promised to make for a more dynamic Navy. If the changing geopolitical climate meant they needed more electronic reconnaissance vessels and fewer minesweepers, the Navy wouldn’t have to wait the better part of a decade to reshuffle their assets; the changeover could happen in a matter of weeks.
It starts with the [Tom Scott] video, the first one after the break. [Tom] is great at presenting fascinating topics in a polished and engaging way, and he certainly does that here. In a darkened room, a begoggled [Tom] poses with what appears to be a slow-moving beam of light, similar to a million sci-fi movies where laser weapons always seem to disregard the laws of physics. He even manages to pull a [Kylo Ren] on the slo-mo photons with a “Force Stop” as well as a slightly awkward Matrix-style bullet-time shot. It’s entertaining stuff, and the effect is all courtesy of the rolling shutter effect. The laser beam is rapidly modulated in sync with the camera’s shutter, and with the camera turned 90 degrees, the effect is to slow down or even stop the beam.
Hoodies are great, and rightfully a hacker’s favorite attire: they shield you from the people around you, keep your focus on the screen in front of you, and are a decent enough backup solution when you forgot your balaclava. More than that, they are also comfortable, unless of course it is summer time. But don’t worry, [elkroketto] has built a solution to provide the regular hoodie wearer with a constant breeze around his face, although his Clean Air Bubble is primarily tackling an even bigger problem: air pollution.
Wanting to block out any environmental factors from the air he breathes, [elkroketto] got himself a thrift store hoodie to cut holes in the back, and attach two radial fans that suck in the air through air filtering cloths. A 3D printed air channel is then connected to each fan, and attached on the inside of the hood, blowing the filtered air straight into his face. Salvaging a broken drill’s battery pack as power supply and adding a 3D printed clip-in case for the step-up converter, the fans should provide him a good 5 hours of fresh air. Of course, one could also add a solar charging rig if that’s not enough.
Keep in mind though, while a wearable air filter might sound particularly useful in current times, [elkroketto] specifically points out that this is not for medical use and won’t filter out any airborne diseases.
[Gosse Adema] has been poking a Microsoft Natural Elite for the last 20 years, and the curvy old girl is about to give out. Looks like he got bit pretty hard by the DIY mechanical keyboard bug in his quest to replace her. Luckily for us, he documented his build.
Where do we start? A first keeb is decently-sized undertaking, but [Gosse] turned it up a notch and made it as low-profile as he could — it’s 2cm thick with the keycaps on. This ultimately meant designing the board such that the anti-ghosting diodes sit inside a cutout underneath their respective switches, which are low-profile Cherry MX Reds. There is no Eagle template for those yet, so [Gosse] whipped one up and milled a prototype PCB before deciding to go the fab route.
The Raspberry Pi Zero W that controls this keeb lives in a separate controller box in the name of slimness. If you are as-yet unimpressed by this build for some reason, [Gosse] even rolled his own firmware, which he explains as part of this epic journey. Seems the only thing he didn’t do was mold his own keycaps, but not everyone wants to type on blanks. We wonder if [Gosse] is aware of the terrifically low-slung Kailh choc switches, although prefab keycap options for those are even more limited.
