VCLFO question

[darren adcock]

Not quite sure how to word this correctly which is probably why I couldn't find what I needed off google

How do I change the sweep/voltage range on the cv out of VCLFO's, been trying to find a circuit, but think I lack the terminology to find what I need.

I've added a diagram in case I'm not making any sense here. The first diagram shows a triangle wave sweeping from -12v to +12v, the second shows a traingle wave sweeping fomr -6v to +6v.

I've attached the MFOS VCLFO circuit I am using also.





Thanks in advance

Darren

 

[Harald Kapp]

How about a simple resistive voltage divider? Vout = Vin /2 should do the trick.

 

[darren adcock]

How about a simple resistive voltage divider? Vout = Vin /2 should do the trick.

Cheers Harald. That's simple enough, passive also. Now I understand why I'm gonna need a LOAD of CV mixers. ;-).... still new to this modular game

 

[darren adcock]

Following your lead I'm looking at this CV mixer with two op amp stages. Am I right in thinking that "offset function" means inverted and non-inverted outputs? If so (just jumping ahead here) it would be really good if both could be selected on a single pot.... if half rotation meant zero mix for either, but pot fully clockwise would mean maximum noninverted mix and fully anti clockwise meant maximum inverted mix. Is this possible?

 

[Harald Kapp]

Am I right in thinking that "offset function" means inverted and non-inverted outputs?

Obviously, although that is not the classic definition of an offset.
The circuit is rather simple:

Potentiometer R3 is usd to mix the outputs of U1 (non-inverting) and U2 (inverting). An optional buffer amplifier may be used to decouple the output from the comparatively high impedance of the potentiometer.

 

[darren adcock]

In fact, been watching EEv opamp tutorials on youtube. Let me see if I can try and figure this out on 5SPICE first.

I doubt I'll be able to figure out a configoration for my Pot question but I'd like to see if I can figure out at least two op amp stages with desired voltage outputs +/- 5v with inverted and non inverted outs.

 

[darren adcock]

Well nearly got there in time before I couldn't resist looking at your circuit. Thanks. I'll work out how to change the values to match my system.

In future I'll try to simulate at least something before asking so I can push my learning.

cheers

Darren

 

[darren adcock]

Oh and thanks for the wiki link, tabbed to read later on at my workshop