Ciat-Lonbarde Rollz-5 Project

Yeah, it’s a mid-supply reference voltage, used to bias the transistor inputs. I think virtual ground is a bit of a misnomer, though, unless perhaps if you always power the circuit with batteries and make sure both rails are always floating.

5 Likes

The schematics look odd because they seem to be drawn from right to left and having positive supplies at the bottom while gnd is at the top, which I assume is not a conincidence. If you reverse that they will be easier to interpret. The transistor at the top right of all diagrams has emitter and collector connected to GND while it it fed a bias current via a potentiometer. That bit of the circuit does not make a lot of sense to me.

3 Likes

I’m really grateful for the work people are doing on this thread (and elsewhere) to turn the pretty but often chaotic Ciat-Lonbarde designs into something a normal person can understand.

5 Likes

This is the 6-Roolz schematic without the Serge section (multi-vibrator)

The roolz power runs counter clock-wise and the resistor values on the Hairy Capacitors descend in Clockwise rotation…

Peter is fucking weird… Some of his stuff makes little to no sense but produces amazing “noise” :smiley:

3 Likes

as for drawing the schematics right to left, I guess I’ve never learned how to draw schematics lol.
So this is the way it seemed correct in my brain… :smiley:

Or are you referring to peter’s hand drawn schematic?

Here is his schematic for deerhorn…


I havent even bothered with this one… lol

4 Likes

@fredrik
Like this?

3 Likes

Yep, that look much more conventional. Although functionally the same, if you’ve been looking at various schematics for a while, you ‘discover’ that there are certain conventions a lot of people adhere to which makes it easier to understand the next circuit you look at and find circuit parts with specific functions.

Drawing a schematic like the curly one is not unlike writing obfuscated code. Functionally that is the same as ‘normal’ code but it is more difficult to read for humans ( not for computers ).

5 Likes

Obfuscation is of course the entire point here.

3 Likes

Yeah, that opamp should give you a nice mid-supply rail. You could probably increase the voltage divider resistor values a bit, but it doesn’t use a lot of current as is, so should work just fine.

(the resistors don’t just form a voltage divider, they also keep the capacitor charged which helps dealing with 9V ripple – if you remove the cap, the opamp will faithfully pass on 50% of the ripple, which is a bit more than the 0.001% or so that makes it through via the opamp supply rails)

5 Likes

I appreciate your responses so much @fredrik :slight_smile: Thanks again :slight_smile:

4 Likes

Well here she be - a complete CV 6-Roll

6 Likes

Looks like an electronic flower!

4 Likes

Looks so dope! Question I’ll ask here cause I’m sure others would find useful as well…how do you rotate components in ways other than 90*? Or get non linear traces?

2 Likes

so there are a couple ways to do it - click on the component itself and hit CTRL + M and it will open a move box for x, y, and Rotate - you can rotate it however far you want there.

Or - CTRL - R on certain components and you can set its rotation in the lower left

I believe in normal view it is CTRL - R and CTRL-M and in Foot Print Editor only CTRL + M works… lol

4 Likes

The non linear traces - I use WireIt for a Plugin and create my own nets. :smiley:

5 Likes

Guys and gals… I present my 2-Roll LFO x8
It works beautifully!


6 Likes

Just make sure the demons you summon with that thing pay rent.

6 Likes

What do the control signals look like? Voltages, pulses or gates, etc.?

1 Like

some of the waveforms are presented on this page -
http://ciat-lonbarde.net/rollz5/

Some raw - some post ultrasound filter.

I am actually getting an old scope hopefully soon, will have to check it out on there - pretty sure my DSO-138 stopped working lol

1 Like

And they are Pulses from my understanding.

When I get into the CV Rollz boards - those will generate CV :smiley:

1 Like