DIY Teensy 3.2 feat. zero-layer 'PCB'

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Long time reader, first time poster. It's been said many times here but I'm a huge fan of the Teensy series -- Paul, thanks for your continued hard work.

I thought you folks may get a kick out of a recent late-night tedious side project. I picked up an MKL04 and a MK20DX256VLH7 (along with a few support components) and put together this absolutely worthless piece of circuit trash:


The white LED... it's on because I was able to load a simple blink sketch, and managed to snap a single photograph of the circuit before it glitched out (and hasn't worked for more than a fraction of a second since). Turns out the already sensitive 16 MHz crystal really doesn't like free-air soldering sans ground plane. But yeah, it's officially possible to build a barely functional Teensy 3.2 clone without a slab of FR4.
That's just awesome. If I ever tried that there would be nothing but blue smoke and tears. Congratulations for making it work!
Now you just need a tiny little tin foil hat over the crystal.

Is actually an interesting case, since I'd have guessed the crystal would work in free space like that. If my physics Fu is working, you'd need to increase the internal loading cap values, trying to remember if they are configurable.

Edit, so you could try tweaking the OSCCR register bits to change the cap settings, though in the teensy configuration that'd be tricky since they'd be first set by the bootloader.
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