The mockup @thonk seems to disagree 
Anyways, thanks for the info 
ohhh got it, didnāt know the levels were diff. cheers Phil
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Yeah, looks like initially we were going to require H/V sync be patched directly each time. We decided to have the switch instead.
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Cadet āPedestalā modā¦ its not the same pedestal like in Prismatic Ray but you can control (kinda) the gradient (+ pwm?) of your Cadet VCO.
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I used one of these switched pots for the pedestal mod in place of the H/V switch so I can still sync the oscillator and change the oscillatorās range. That switched pot is a little bit too big so you have to solder the legs of the other pots and switches where the PCB is flush with the panelās edge for it to fit.
Really worth breaking that R6 trimmer out along with the square wave output on J3.
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how hard would it be to modify the Scaler for 10V to 1V? I would like to interface my buchla modules with the Cadet series.
totally, yeah, I am currently using attenuators. Wasnāt sure if it was as easy as, say, halfing the values of the resistors used without choosing different op amps.
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This should be quite achievable. Looking at the schematic, R4/R1 (etc) is a voltage divider which divides the input voltage, but it also acts as a termination to ground for the input signal (which will generally be driven from the output op-amp of another module through 499R) so the resistor value calculations are more complex than they at first appear (and probably why some of the BOM and schematic values differ). Your best bet is going to be experimentation - I suggest you solder in some single pin sockets (e.g. https://www.taydaelectronics.com/30-pin-dip-sip-ic-sockets-adaptor-solder-type-single-row.html) for the resistors and then you can easily try different values until you find one that works the way you want. If you donāt have a range of resistors already then grab a āresistor assortment packā for a few dollars. Stick to values similar to those specified for the 5V->1V version, and either increase R1 or decrease R4. Informed trial and error is a great way to learn DIY!
Definitely no need to change the op-amps.
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R1 and R4 set the attenuation. R11 and R12 set the gain. R30 and R31 set the offset voltage.
For calculations, look up non-inverting opamp amplifiers.
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Just finished building a set of cadet modules.
(As an aside big thank you to everyone posting here!! Browsing this forum has been incredibly helpful both for the building process and in starting to understand the wonky world of video synthesis!).
Playing with the oscillators I do wish they were just a tad slower at their slowest setting. Based on the schematics it looks like R2 is the resistor to play with, is that right?
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First thing to try is plugging a DC offset, e.g. from a Cadet Processor, into the CV input or mixing it with your other modulation. When vertically synced, my VCOs usually show about 1 bar with the Frequency knob fully CCW and with a DC offset from Processor, I can get it to go as slow as ~1/4 - 1/2 of a bar. Horizontally synced (EDIT: oops, unsynced), Iāve been able to get down to some somewhat slow pulsing LFOs.
I havenāt tried modding that resistor but it seems like a reasonable place to start experimenting! You could just install some pin headers in its place and substitute values close to 16.5k on either side to see what the effect is. Let us know what you find out!
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Thanks for the reply!
Iāve played around with using the the processors to get extra range out of the oscillators but was thinking Itād be nice to free the processors up for other duties. Though as Iām getting to know this system I find that I often run modulating voltages through a processor anyway so maybe itās not such a loss.
But, curiosity will probably get the better of me & it seems too fun to poke around in the circuit to not! Iāll report back with any findings.
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Looks like R2 will change the maximum frequency of the oscillator, but not the minimum. Using a lower value will increase the maximum frequency and vice-versa. It could of course be that itās changing both but the effect is much more pronounced in the higher frequenciesā¦
Either way though I donāt think this is the solution Iām looking for - the range of the oscillators feels pretty right, I was mostly looking to get the lowest frequency (without any modulation) to sit a little below one cycle.
Back to the schematics 
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you could make a simple adjustable voltage source design to mod the CV input of the VCO
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Thanks for the pointer on this! I put this together on breadboard today and it works great.
I probably should have been less lazy and set the voltage divider to exactly 0.5V but it seemed close enough with the resistors I had on hand.
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As far as I understood so far the mods allow PWM only on the triangle wave (via Pedestal MOD or Cadet 8), is that correct? is there any way to get Sine out somehow?
Youād need a separate triangle to sine shaper. Thereās some good starting points here:
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