Differentiator VC Feedback Project

OK next Proto pcbs are ordered.
The previous ones did work, but lacked a voltage shifting stage

the new proto has that stage, with CV
so it has 2 CV inputs, one for feedback level, one for voltage shifting (which results in different types of feedback patterns)

I did a promo video on Vidicon , I’ll post the clip next week.

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That sounds perfect Martijn :+1:t3:
An XY joystick module sounds like a really good controller for this.

Sadly I caught very little of the talks on the Vidicon programme but I’m looking forward to seeing the video of your demonstration.

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Ace! Want a kid as soon as possible :drooling_face:

The effect briefly at 6:36 was great looking but adding colour at 8:28 looks super awesome :star_struck:

first screenshots (photos of the CRT) of proto v2
the input is a hard edged diamond shape (2 ramps into a Hardkey Generator),
modulator is a Cadet VCO with H or V lines selected.

A large range of iterations is possible, so that is cool.
I have to finetune a lot of functions and test everything, but it looks pretty already!





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A bit of a breakthrough today! I needed that.

the new and simplified breadboarded schematic now works as intended
So I’ll do one last proto and then maybe add some features I’ve been thinking about …
routing 1 2 3

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the new proto is working. I’ll add a hard clipping stage because the cool patterns need higher voltages
I’ll probably use the clipping stage of the LZX Encoder.
The bottom (-v) is already clipped correctly by a 1n5711 diode inside of the mixer stage

new feature set:

Potmeters:
neg mix
pos mix
gain
cv att

switch
edge width

jacks
input
CV
output

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ok, another prototype, v4c

things are almost good now. it needs some minor fixes.
I’ll test more this weekend

The output looks really cool. lots of sweet spots :slight_smile:

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Really glad to see this coming to fruition, would be cool to see any other captures you’ve found during recent testing!

yes, I’ll make some recordings in the weekend :slight_smile:

just a minute ago I made myself look like Pinhead
camera input → edge modulated with several horizontal bars = spikes!

I’ll experiment with several highpass caps to see what works best / edge width

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finally some updates!

v5 works, it has some really nice results. with a middle ground between controlled rounded feedback and glitch
the added send/return path for the feedback is pretty cool

I had a few new ideas for this module (expanding it with more inputs and filters)
so it is an ongoing project :slight_smile:

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i’d love a kit when this is ready! keep up the great work!!

Me too super curious!

Also super excited about this amazing project and would love a kit/pcb/gerber whenever it’s ready! <3 Very close to finishing the Cadet build…it’s been a bit of an Everest for my neuroverge ass but it’s coming together:) Also as an aside anybody privvy to cheaper stock of lt1251’s r lt1256’s that arent a bajillion dollars a unit (well $16)? Cheers and excited for this project!

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Octopart is your friend but you can always expect LT125x to be expensive compared to most other ICs used in DIY video modular.

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Thank you for the swift reply! Yeah I definitely figured. Off to mouser :)))

or Octopart! (first time hearing of it! cheers)