[Carl] wanted to put his force sensors on a transparent PCB and had to ask his board vendor for a special sample. Flexible PCBs are available on transparent substrates made of PET, but they are not as common as polyimide boards. As [Carl] found out, these boards are a bit thicker, a bit less flexible, and don’t hold up to very high heat as well as the standard boards. Undeterred, he designed a 3D Christmas tree using the clear boards. The result that you can see in the video below looks pretty good and would have been hard to duplicate with conventional means.
When you build the board it is as a flat spiral, but lifting it in the center allows it to expand into a conical tree shape. The circuit itself is just an LED blinker, but the flexible board is the interesting part.
At risk of getting any ASMR buffs who might be reading cranky because there’s no audio, [Chris], or [@no1089] on Twitter, has gifted us with this visually stunning scan of his Maxim MAX86160 in-ear heart monitor mounted on a rigidflex PCB. You can take a look, in the video below the break.
If you’re wondering why anyone would scan a board, other than boredom, know that it’s actually quite common. X-Ray machines are commonly used as a quick, passive way to check a board that’s fresh off the production line. These aren’t the X-Rays like those of broken bones you’re (hopefully not too) used to seeing though, they’re Computed Tomography scans (CT scans, CAT scans), in effect just 3D X-Rays.
For electronics manufacturers and assemblers, CT scans are incredibly useful because they provide a non-destructive way to check for errors. For example, how do you know if that middle BGA pin is actually soldered correctly? You could run a functional test and make sure everything is working (at least, everything you check), but that takes time. The longer it takes to validate, the higher the manufacturing cost. In manager speak: “cost bad. Fast good.”
It’s also common to use a CT scan to create a full 3D model of a board. This makes it easy to check every little detail, especially the ones that are visually obscured by surface mount devices or critical signal paths that are buried under board layers.
But we know you really want more of this video, but better. And we’ve got the goods. For the chill folk among you, here’s a 55-minute version without all the CT scan info cluttering the screen. For those of you currently blasting eDM in your headphones, here’s a 30 second clip of it looping at ~5x speed. Eat your heart out:
Liner notes? Passé. In Berlin, the release of a special edition synth-wave record came with an accompanying experimental synthesizer called Wired Heart.
At the core of this adorable heart-shaped synth, designed by music technology enthusiast [tobi tubbutec], is the classic 74HCT14 chip with six Schmitt trigger oscillators. The bright red PCB has eight gold touch and humidity sensing pads that activate and modulate these oscillators. As well as changing the sounds by playing with pressure and conductive liquids you can use the six sets of header pins on board to plug in your own components for noisy experimentation. Wired Heart ships with LEDs, photoresistors and a potentiometer, but we’ve also plugged our own DIY fabric pressure sensors into this synth to make some excellent electronic sounds.
In the Hackaday.io post linked above, [tobi tubbutec] walks us through a number of the circuit design decisions he made while prototyping his “cardiotronic human-touch hexoscillatric stereo esoteric snythespacer”. We enjoyed his creative and sometimes unconventional designs, from his inclusion of non-functioning traces for aesthetic reasons to his chosen method of hard syncing — injecting a small pulse of one oscillator into the other. If you want to examine his layout in more detail, [tobi tubbutec] has helpfully included the KiCad schematic file in his write up.
This adorable, hackable synth caught our eye at this year’s SuperBooth — an annual indie electronic music conference in Berlin that’s well worth checking out if odd noises and handmade electronics are your thing — but it’s recently been listed on Tindie too. To listen to the upbeat synth-wave record Wired Heart originally shipped with, visit the artist Hyboid’s bandcamp.
Badgelife and the rise of artistic PCBs are pushing the envelope of what can be done with printed circuit boards. And if you’re doing PCB art, you really want to do it with vectors. This is a surprisingly hard problem, because very few software tools can actually do DXFs and SVGs properly. Never fear, because [TallDarknWeirdo] has the solution for you. It’s in Eagle, and it uses Illustrator and Inkscape, but then again this is a hard problem.
The demonstration article for this example is just a Christmas tree. It’s somewhat topical green soldermask is standard, FR4 looks like wood, and silver and gold and all that. [TallDarknWeirdo] first split up this vector art into its component pieces — soldermask, bare FR4, and copper — then imported it into Inkscape to make the SVGs. This was then thrown into an online tool that creates something Eagle can understand. The results are better than importing bitmaps, resulting in much cleaner lines in the finished board.
Quick word of warning before we get into this, though: if you’re reading this in 2019 or later, this info might be out of date. Autodesk should be releasing a vector import utility for Eagle shortly, and we’re going to be taking a deep dive into this tool and complaining until it works. Until then, this is the best way to get vector art into Eagle.