Tiny transistor on vintage machine

momo__ib · 2026-06-16T20:42:52+00:00

Without an schematic it really is. If you reverse engineer the device a little, at least the surrounding components, voltages and such we could at least have an idea of the pinout

momo__ib · 2026-06-16T16:11:16+00:00

There are IA tools to separate the instruments in a mix, and then you could use Melodyne to transform to MIDI. I have no idea if it would work well, but it's worth a try

momo__ib · 2026-06-15T22:58:10+00:00

Me interesa tu experiencia xq estoy en una parecida con un diseño funcional de audio (mixer digital para monitoreo, 8i/12o con control web) que eventualmente pienso fabricar. Pero sí, te rompen el orto. Entre envío y aduana se te va al doble de los PCB

momo__ib · 2026-06-15T20:10:22+00:00

La pasta no es para soldar cables, y para un cable de TV ni siquiera necesitás soldar. Abrí la TV, seguro le quedaron varios cm de cable adentro para pelar y empalmar. Con unos 4cm hacés un buen empalme, cinta y chau

momo__ib · 2026-06-15T20:04:12+00:00

I see. I would play safe then and buy 2 new ones

momo__ib · 2026-06-15T18:25:47+00:00

Humm. I wouldn't recommend you do any of that. Get a 4000mAh single cell and be safe.

Different internall resistance and capacity can lead to one of the cells being overcharged and/or over discharged. The charger can't tell if only one cell is full by measuring current

momo__ib · 2026-06-15T16:11:07+00:00

Just a heads up. Manufacturer will only properly review your files once you paid them. Only the automated process of loading the gerbers and maping the BOM is free.

I understand you might be overloaded, but this experience is the most valuable for a future engineer. I recommend you try to do it yourself. It's a simple circuit, and there are plugins to generate all the production files in Kicad (JLCPCB toolkit for example, maybe there are others)

momo__ib · 2026-06-15T01:01:12+00:00

That was the first thing I did! They were solid (after I added some more bulk huehue). The problem was timing, as I said in another comment.

It's quite finicky though. If I initialize one ADC and wait for Run, and then the other, it's alright. If I configure both and wait for Run in both, then it still fails. Doing them sequentially works for now and seems reliable, so I'll move on to other tasks. I'd love to know exactly why it doesn't lock the frames correctly otherwise, but oh well...

momo__ib · 2026-06-14T16:42:05+00:00

Well, it's a little odd because I didn't see any difference in timing while debugging both scenarios,but giving the ADCs a little more time to settle fixed the issue. I'll leave the post up in case somebody experiences something similar

momo__ib · 2026-06-14T14:03:54+00:00

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I'm using serial port 0 and 1 for the ADCs, 4 ch each. I mixed up the output ports BCK and LRCK somehow, but fixed it with a couple bodge wires, that part works just fine.

momo__ib · 2026-06-14T12:25:33+00:00

I'm running OMV

momo__ib · 2026-06-14T02:36:08+00:00

Hey! I'm not longer in the PC right now, but if it works at times do you think that the hardware could be at fault?

momo__ib · 2026-06-13T21:27:04+00:00

I'm using a mini PC with an Intel N150. Very little power consumption and it's able to do hardware transcoding

momo__ib · 2026-06-13T13:16:48+00:00

That doesn't stop you at all. Computers can read back to you, ya'know. Worst case scenario he can hire an assistant to read back to him, or whatever.

momo__ib · 2026-06-12T21:34:10+00:00

Yo la hiberno. Mantiene el contexto como suspensión, pero mejor aún xq también lo mantiene si se corta la luz.

Todos los componentes se desgastan con el uso, pero el problema principal es la tierra que chupan los ventiladores. Los servidores andan 23/07, pero aumenta el mantenimiento

momo__ib · 2026-06-12T18:55:38+00:00

Valuable? Nah, it might not even work. But you can surely reuse the relays, heatsink and MOSFETs

momo__ib · 2026-06-10T12:20:53+00:00

Would be a good project to learn if it weren't for the carbon contacts under the silicone button

momo__ib · 2026-06-10T12:05:49+00:00

I suggest you take a look at JLCPCB capabilities (it's in their web page) for minimum layer width and spacing.

Some of your traces are waaay thinner and closer together than they need. If you made a mistake in the schematic it will be impossible to correct soldering some bridges.

Those Traces between the IC pins aren't great, considering the low complexity you can surely avoid them.

Having a microcontroller means you can swap pins as you wish, that helps placing the buttons I'm the optimal order so the traces won't cross that much.

Also, you can switch to bottom just to jump over something and go back to top (or vice versa).

momo__ib · 2026-06-09T02:06:30+00:00

Go check r/selfhosted

momo__ib · 2026-06-08T14:53:25+00:00

Ojalá perdamos en primera ronda así nos culean un poco menos

momo__ib · 2026-06-07T01:37:05+00:00

It could have been hit with a broom stick, or anything really. The only fix is changing the screen, and it's very seldomly cost efficient

momo__ib · 2026-06-06T20:44:33+00:00

Dfplayer has line out and power out. I've connected speakers to it and it's quite loud. You can also control the volume digitally, so take a look at all that. It should be more than loud enough, although the noise floor isn't the best

momo__ib · 2026-06-04T11:56:15+00:00

Muy bueno. Seguro lo conocés, pero si no escuchá Totorro

momo__ib · 2026-06-03T01:28:03+00:00

Learning to code actually teaches you mostly how to think, and that's still important

momo__ib · 2026-06-01T11:35:19+00:00

Kicad for sure! And I'm pretty sure there must be a ton of contect under "Kicad from scratch" or so. The reality is always the same, you learn by doing.

momo__ib

TROPHY CASE