I think™ you could probably make a workable quadrature shaper with the IX and some analog switches and a comparator. (You can split the triangle from the IX into four separate “zones” and then offset and invert as needed to stitch it back together) This works at audio rates, but the switching might be a problem at video rate.
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Alternately, invert-chop the TRI into a SAW (Which can trivially be wavefolded back into a TRI), offset it (by a CV-able amount), and then fold it back. if the wavefolder is precise and fast enough, this would give you a new TRI with controllable phase offset. As with the other approach, this depends on speed and precision to work glitchlessly
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I tried that gamma trick, (triangle VCO to Multiplier CV & input) . it gives a very nice waveform.
This definitely goes into the next vco pcb!
@transistorcat
how can you chop a saw from a triangle and get the full range? I patched it with a squarewave into the Fader, but that gives me a half saw (1/2 of the triangle)
I also did the pedestal mod , it has interesting effects on the shape and frequency.
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Fade with the square between the TRI and an inverted and offset TRI. (flip the tri around on the down slope).
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would this be possible with patching, you think?
Vco (with squarewave mod), Fader & Processor / Multplier ?
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I think so? mult the tri to fader A and processor, turn the processor amount fully ccw, plug processor output to B, SQW to fader in and adjust the bias on the processor until to get it matching (I think you want the bias to post and fully clockwise). Be aware that this gets you a 0->2V SAW, so either adjust the amplitude with another processor or adjust the input amount on the next module in chain accordingly
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Note that if you’re redesigning/modding pcb’s, remember that you can swap the expensive/rare fader parts an analog switch if you’re not actually fading inbetween the extremes. (for example for the tri->saw)
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I may get back to you about that when I do the layout. Thanks!
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With the retirement of Cortex, how about something like this?
Want to get me some of that clean component output.
Put a NTSC/PAL dip switch on the backside, since most users probably set it just once? Add RCA sync?
Have been dragging my feet on a Cortex, since I already have a Vidiot. Now thinking TBC2 + Marble Index + Diver + this would be a perfect Cortex+ replacement.
(Also seems like this would take pressure off including component out on the upcoming Automata standalones.)
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That doesn’t seem like it’d be a very hard module to design. If you check out “Circuit Diagram 4 (RBG to YUV)” at the very bottom of this YUV to RGB page, it looks easy enough and is using pretty normal parts (no not-in-production ICs). It’s just some analog addition and subtraction, after all. The circuit on that page looks to me like it’d be pretty close to what you’d need. I think you could cut out the LM1881 entirely and just use the sync signals from the cadet 14-pin sync. Also, you’d want to replace the power bit with the power bit from a Cadet/Castle module. I’m not 100% sure about the inputs and 4053… The 4053 seems like it’d be a good idea, to ensure no stray inputs bleed into the sync portions, if I’m understanding it correctly.
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Wish that I had the skillset to make it happen (or the time to learn) but alas not at present. Fully admit that my hope was/is that it is an easy enough project that someone might take it on (if not LZX themselves). Never really thought there would be much interest in such a thing while VC was the standard base module, so hadn’t mentioned it before. In a post-Cortex world, perhaps such a module starts to make sense?
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