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I learned PCB design, 3D printing and C just to listen to music

139 points by interfeco

by mananaysiempre

2 subcomments

> Once I had the design [of the enclosure], I tried to 3D print it on my brand new 3D printer, which turned out to be a disaster. Took me some time to learn more about designing for manufacturing, especially for 3D printing.
Would have been nice to hear how specifically it was made to work in the end.
> Turns out, cross-fading two 4MP images at 60 frames per second on a moderately powerful single board computer is not so easy.
Yeah, at first it feels stupid that every pretty LCD screen for bus or train stops, ads or whatnot has a full computer behind it, but then you ballpark the memory bandwidth and realize you need a ~ 1 GHz device anyway just to be able to chew through the pixels fast enough. (1920² px × 24 bpp × 60 Hz = 620 MB/s.) You also realize why “fill rate” used to be such a buzzword 20 years ago and why it took a while until true color became ubiquitous.
On the flip side of the O(n²), you can easily drive a watch-sized display with pretty good ppi using a 32-bit MCU, which is why the Apple/Google/Samsung battery-guzzling approach to smartwatches seems wrongheaded to me compared to Pebble/Zepp/etc.

by interfeco

3 subcomments

Hey HN,
I've finally finished my dream music streamer featuring a vinyl-sleeve-sized square display, a custom carrier PCB for a compute module and a 3D printed case, running a custom-compiled kernel, Alpine mini rootfs and a small C app driving the display.
I did not think that this was doable by a hobbyist at all, let alone using free/open source software only (KiCAD, FreeCAD, VSCode). Turns out I was wrong!

by matheusmoreira

6 subcomments

> I never did this before so there was plenty to learn, from basic electronics and magnetics to high-speed signal routing.
How did you learn this?
As a hobbyist I found hardware to be quite impenetrable, given the hard mathematics and physics requirements. My attempts to learn this essentially degenerate to taking an informal engineering course. It quickly becomes clear that I'm years away from making something, and I eventually run out of both free time and executive function. AI's been helping... But I don't have the ability to tell when the output is wrong.

by peteforde

1 subcomments

This is really cool. I would love to switch from using the SoM I'm currently using to the Radxa CM3 but I cannot find even a single unit actually available for purchase on any of the "international" distributor options.
Can you speak to how you're sourcing these, and from where? (And would you sell me one?)

by websap

1 subcomments

> I use AirPlay in my home exclusively, so I needed this streamer to support that
Doesn't Airplay switch you to other media on your device (e.g. Reddit, Youtube, etc) while browsing while streaming?

by dsign

2 subcomments

A bit tangential, and in the topic of nostalgia for old ways, remember when every block had a photo shop? Couldn’t we get a “PCB shop” in our bright near future? I wonder if the density of enthusiasts that need PCBs made is so low that the entire market is captured by only one or two companies based off China subject to the realities of shipping times.

by PcChip

1 subcomments

Did you configure pipewire to allow multiple samplerates, so it can auto-switch the dac and not have to resample?

by reolbox

1 subcomments

How did you learn PCB design? Any books or resources you can recommend? How long did it take you to learn?

by rebolek

0 subcomment

by kubb

1 subcomments

> I was able build an out-of-band protocol extension into my audio player app
I wonder how that works.

by jdsfijfdsifs

0 subcomment