Psuedo random LFO schematic?

[nirvanas silence]

I found alot of great info on a page from Geofex but there were no reccomended starting values or formulas for finding the right value so I'm curious if anyone has experience with this.  Thanks for any tips.

[The Tone God]

Are you talking about a smooth LFO like for a phaser or a random digital LFO for sequencers ?

Andrew

[nirvanas silence]

Not a smooth LFO.  Here is the link I was referring to.  I just basically want to know how to figure out what values to use for the parts.

http://www.geofex.com/Article_Folders/LFOs/psuedorandom.htm

[The Tone God]

There are probably no values for the same reason I don't include values on some of my schematics. The values depend on what you are looking for. What are you trying to drive with this LFO ? What range are you looking for ? Since the oscilator circuit R.G.s is using if pretty common and is in the datasheet there is usually simple formulas for calculating the speed.

Andrew

[Paul Perry (Frostwave)]

Try 200K and 1 uF, multiply or divide the cap by 10 or so until you get what you wnat.

[nirvanas silence]

Ok great, thanks to both of you guys, I appreciate it.

[Paul Perry (Frostwave)]

http://www.cgs.synth.net/modules/cgs21_super_psycho.html

Ken Stone's Psycho LFO here will give some starting points as well.
Also, he sells boards!!!

[amz-fx]

Here is the noise circuit from the Roland TR606 drum machine.  You can filter this noise source to get a low frequency signal:



C92 is the output and I would make it 1uF if you're going to low pass filter it.

If you gate this noise source you'll get a noise splash like a cymbal, or you can sum it with a drum sound for a snare sim.

regards, Jack

[R.G.]

Like I said, the more non-correlated oscillators you add, the better the noise.