WIP [experimental Painter]

Forum DIY
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The first prototype is ordered!

The idea is to make a sort of posterize module (as featured in the Panasonic MX30 and the likes of), but with a lot of control.
So I made a design with 5 layers, which are 5x comparators with width and strength controls.
They can share the same input (they are normalised per input), but can also have their own input (for experimental stuff)
The outputs are routed into a R2R ladder and through an amplifier.

The first proto will test if this works as intended.

The next proto ideas:

  • voltage control over all stages

  • separate outputs for each stage

  • sandwiched pcbs

  • sequenced comparator output (5 step 4017 + 4066 gate)

  • SMD & ADA4851 (instead of LM6172)

If you have any tips or feature ideas, let me know!

picture: big pcb for testing. the final product will be smaller!

image
image602Ă—804 45.5 KB

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I’m curious to see how you’re going to get the +/-5V for the ADA4851. I’ve been thinking of switching from LM6172 too, but I haven’t tried figuring out a good eurorack to +/-5V method yet.

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7805 / 7905. Many of the cadets, castles and expeditions use these and they come in a wide range of footprints and currents. Sometimes “traditional” isn’t all that bad.
I’m using them on all of my yet-to-be released SMD modules.

example

njfagfi7es
njfagfi7es1920Ă—1440 229 KB

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I was a bit concerned about the efficiency (and thereby heat), but guess you need to draw quite a bit of current (for an analog circuit) to get the 7805/7905 pretty hot.

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I was going to post asking if something like this existed! Questions:

  1. This is monochrome, right? So for RGB, we would need three of these.

  2. Are the comparator thresholds voltage-controllable?

  3. Can it handle 1080i?

  4. Will someone be building these? I’m not competent to build this myself.

THANKS!!!

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All signals in a video synth are monochromatic until they reach an encoder. If you want to process three voltages at once to plug into the RGB inputs of an encoder, yes you would need three modules as there is only one Out jack in the proto image above.

This is answered in the first post.

Yes. There’s nothing in the above posts that says it depends on synchronization signals so the resolution and timing of your system is irrelevant for this purpose.

This doesn’t exist yet as it’s a work in-progress as noted above. Martijn almost always provides built versions of his designs if you message him when an order thread is posted.

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I’m buying, take my money! Seriously, when will this be ready?

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Thanks for answering my questions. Reading a PCB diagram is not one of my current skills. So I don’t know what I’m looking at. How many ins and outs, knobs, switches, does it need sync? I have no idea.

Also wasn’t sure what the word “stages” meant in this context. Processing stages?

It’s great to hear that prebuilt modules will be available. This precisely meets the needs of what I am trying to accomplish!!

I was going to ask for a four-level keyer like the EAB Videolab, but five is even better!

Five stars

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Also, just realized that I will need six of these. Looks like I’ll need another rack! But it will be epic, I’ve already got a couple of Triple Function Generators.

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Will there be separate outputs per comparator?

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Welp, I can’t read, apparently.
Looks like a thing i will be wanting

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the first test of the prototype looks good!

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update:

  1. The r2r dac works but I don’t like the looks. I’ll try a sort of active mixer config next.
  2. I miscalculated the range limitation resitors of the comparators, so that needs fixing (made a sim already that works much better)
  3. I want to add a sort of sequenced output , going to check if that will work with a 4017+4066. this also will need some syncing I presume

There is some overlap with another project, so they might merge. We’ll see :slight_smile:

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