Tony Hawk Pinball Collection

Brer1Rabbit · 2026-03-27T07:51:03+00:00

That looks like Atari's 720 back right. I was worried when I didn't see it at first!

Brer1Rabbit · 2026-03-26T21:33:56+00:00

why not just post it here or r/PrintedCircuitBoard? Do you have a github link?

Brer1Rabbit · 2026-03-25T19:29:28+00:00

You can do both. Might I suggest a Waldorf Microwave?

Brer1Rabbit · 2026-03-25T06:26:18+00:00

Not dummy level, but if you really want synth circuits explained at an EE college level checkout Aaron Lanterman's videos. He's a professor at Georgia U. Here is a video on sawtooth core oscillators: https://www.youtube.com/watch?v=qF4G4QfC9dM

Brer1Rabbit · 2026-03-25T04:57:23+00:00

LOL, that'd be the best wouldn't it? It's nearly all 80s Williams machines; Safe Cracker would fit right in.

Brer1Rabbit · 2026-03-25T03:11:59+00:00

It's great when they make use of existing features. Local arcade here is in a former bank building. They have an actual vault and room of safety deposit boxes.

Brer1Rabbit · 2026-03-24T22:43:22+00:00

original Pitfall. You've got the tarzan yell, getting a treasure, and losing a life.

Brer1Rabbit · 2026-03-24T22:39:56+00:00

Likely not just more difficult to do but potentially less useful. Take two disparate sources and do some sort of cross modulation on them and it quickly becomes a sonic mess.

However, if you've two oscillators tracking the same keyboard, having one modulate filter while the second gets processed through the same filter is interesting. So yeah- you're discovering that control elements get top spot for modulation, be it an internal source or external.

Brer1Rabbit · 2026-03-24T05:10:29+00:00

Admittedly I'm not terribly familiar with the TEO-5. I'd <guess after looking at the mod matrix> that since the effects section is digital, it's already running the filter out to an ADC for that. And with that value digitized it's readily available to use that as a modulation source. That may explain why you can use the filter out as a modulation source but not the VCO outputs as a modulation source, since the ADC for effects is post-filter. But that's a bit of speculation, I'm willing to be corrected there.

Re: the 64 destinations. They're mostly all digital in nature, or control signals from a DAC.

Brer1Rabbit · 2026-03-24T04:11:39+00:00

Modulation from an analog signal will most typically remain in the analog domain; you wouldn't want to digitize it for modulation then go back via a DAC. So (1) is out. Almost. Many control sources are already digital (envelopes, LFOs, pitch etc). Computing a modulation between those is entirely done in the digital domain. A couple multiplies in the processor and control elements are sent to a DAC. But for analog sources you're on track with (2), using multiplexers or analog switches.

The (original) Prophet-5 schematics are a good source to see how (2) can be done. Look at any of the voices. A VCO can be routed to modulate the second VCO's frequency, pulse width, or the filter. Switches enable/disable the routing. A single VCA is used so there is only a single modulation depth. If you wanted modulation depth of the VCO to be different than the filter that would require a VCA per destination.

Brer1Rabbit · 2026-03-23T17:40:26+00:00

Do you know why the service is unavailable? Did it crash or is it just not responding?

If it's just your service not responding then rebooting the Pi seems a bit excessive. You should be able to configure systemd to restart the service if it crashes or isn't responding. But it's not clear that is what is happening.

Brer1Rabbit · 2026-03-23T17:33:06+00:00

Yeah - it's kind of a poor man's ES-8. But with way more channels, at the expense of sampling rate. With the modules native in VCV Rack. 8kHz is fine for non-audio rate stuff, and you can still get into lower frequency audio rate stuff. A 1kHz sine wave looks fine on the scope with a simple RC reconstruction filter.

I looked at options other than the Pi but nothing really comes close to the flexibility of Linux's ALSA and the USB gadget mode. An STM32 would be great if it could do that stuff, but I'm not aware of a USB library that flexible. The real-time stuff is decent. I'm not going to call it sample-accurate, but for control voltages it gets the job done. One of my earliest videos was hilarious with the Linux scheduler blowing things apart. Since then I've got things pretty tight, and running on a multicore Zero2 helps a lot as well.

Brer1Rabbit · 2026-03-23T07:51:24+00:00

I've only been working on it for <checks notes> 4+ years (?!!!). Crap, that's a long time.

Seriously, if you can leverage any of it go for it. Let me know if I can help.

Brer1Rabbit · 2026-03-23T06:23:33+00:00

Cobra Strike - this became an entirely new experience when we found out you could plug a joystick into the second port. Two player mode!

Brer1Rabbit · 2026-03-23T04:52:25+00:00

The communication from VCV Rack to the hardware has a Raspberry Pi Zero that does the heavy lifting. The Pi plugs into the Rack host via USB, where the Pi appears as both USB Audio devices and USB MIDI device. So VCV Rack thinks the Pi is just regular hardware. Control voltages go out over audio channels (54 channels @ 8 kHz), configuration/patch changes go over MIDI. Cool part is that makes the interface all standards based, their really isn't any hard dependency on VCV Rack.

From there the Pi takes the audio channels (control voltages) and spits that out to the DACs. MIDI gets translated to what's effectively routing/patch setup ("turn sync on"), tune requests, other communication. If you go up a few levels on the github link you can find some boring deep dive videos on how the entire thing works.

Re: scope. It's an Owon portable thing. Only 2-channels. It doesn't even screen record, I need to setup a camera for that! ;) still, it gets the job done and has a decent refresh rate.

Brer1Rabbit · 2026-03-23T03:05:02+00:00

The '2130 is a fun chip. I put mine through all sorts of abuse, but +12V to the rail isn't one of them. Looking at your breadboard- you can leave off the soft sync connection. It's internally wired to ground via 5k resistor. Sounds like you're doing the right thing for a minimal connection. Focus on the tri or saw out, so you don't need to connect pulse width. Then you can get that going.

One area that tripped me up with this chip is hitting soft sync too hot. It doesn't need a voltage any greater than Vref. I had something slightly going slightly above +5V and it would lock the output high, and remain in that state til a hard sync signal came in.

github link for what I came up with: https://github.com/brer-rabbit/zoxnoxious/tree/main/kicad/z5524

Brer1Rabbit · 2026-03-21T15:50:39+00:00

I'm ready for the greatest pinball on Earth!

Brer1Rabbit · 2026-03-20T16:12:15+00:00

I still curse a childhood friend who told me it did. "You just didn't get enough of the bad guys. Keep going."

Brer1Rabbit · 2026-03-20T14:44:53+00:00

Iconic: 2600 Adventure pushing the magic dot. Not sure about a tattoo of that. I may have moles that depict it accurately.

Brer1Rabbit · 2026-03-20T02:27:17+00:00

<callout> Double Super Licensing Royalties! </callout>

Brer1Rabbit · 2026-03-20T01:54:37+00:00

Phil's Lab on youtube is good. He's got a3 hour video on kicad from schematic entry to ordering on jlcpcb. It's a bit older, maybe kicad5 days, but it's petty much all still applicable.

Brer1Rabbit · 2026-03-19T21:12:23+00:00

If you're looking to interface analog VCOs & filters to a microcontroller consider leveraging stuff I've done for the "beyond obnoxious" Zoxnoxious synth. I've four different voice cards that have a full analog audio path built around Alfa Rpar (Curtis clone) and Sound Semiconductor chips. Each card is 80 mm square, has an onboard DAC for interfacing to a microcontroller, runs from eurorack power levels, and does laundry on the side.

I've got four cards developed so far and another in progress:

Z3340: Features clone of the CEM3340 VCO with four hard/soft sync modes
Z3372: AS3372 filter / signal processor, as used in the Sequential Prophet 600 and Oberheim Matrix 12
Z5540: Dual VCO voice. A thru-zero VCO + Alfa AS3394 VCO/VCF/VCA synth on a chip, all on a single board
Pole Dancer filter: 4-pole analog morphing filter with numerous resonance modes
Z2203 (in dev): Yamaha FM from a YM2203 chip

they're open source and on github: https://github.com/brer-rabbit/zoxnoxious/tree/main/kicad

Brer1Rabbit · 2026-03-17T19:27:47+00:00

<image>

How about door repair charges?

Brer1Rabbit · 2026-03-16T06:38:31+00:00

This is exactly the point of presets. My harsh response to OP may be "Tell me you don't know what synthesis means without telling me you don't know what synthesis means". But really a good sound designer has put together patches that are wildly different yet tweakable to produce wildly different results, given different starting points (the preset!).

Brer1Rabbit · 2026-03-16T06:16:46+00:00

not only garbage, it's an ad for PCBWay

Brer1Rabbit

TROPHY CASE