[aryik]

Honestly one of the coolest things I’ve seen on HN. It’s a great display of a ton of things that have just recently (10-20 years) become accessible to the masses. 3D printing for the enclosure, the internet for the schematics, and advanced prosthetics to translate the muscle signal into voltage combined with tried and true technologies like relatively simple circuit design and modular synths. Thanks for sharing!

[mhh__]

The thing that's really struck me (which is potentially saying a lot - or nothing - because I'm still young) is how cheap PCB Fabrication (and Assembly!) at a hobbyist level has gotten recently e.g. An 8-layer ENIG, double silkscreen, a few gold fingers for $40 to $50 shipped is pretty damn cheap

Think of all the projects to never get round to making!

[takeda]

I don't think making PCB was ever expensive, perhaps making a professionally looking one.

In old times you had a piece of plastic with a copper layer. You put wax on it, then you could use a needle to remove wax in right places (you basically print the inverse of the circuit)

Place that PCB in acid, and after the copper gets dissolved you clean it up, and have printed PCB.

There are many techniques people have, and modern ones involves printers, but you kind of always could do one at low cost. It might just not look that nice.

[kube-system]

Doing a complex 8 layer board would have been traditionally expensive... or nonexistent, depending on how long ago we’re talking. DIY accessible stuff is usually single layer or dual layer through-hole stuff.

[takeda]

my bad, now after reading your comment I noticed the 8 layer. Yeah I meant only simple PCB.

[john61]

"advanced prosthetics to translate the muscle signal into voltage". This is not new. Myoelectric controlled arm protheses were developed and in production already in the 1960ies. https://eduard.horvath-vienna.at/ot2003.140-141.pdf