[sdiy] Thomas Henry XR-2206 VCO Page Up

[René Schmitz]

René Schmitz wrote:
> Scott Stites wrote:
> 
>> Nope, just the four op amps listed is all we tried.
> 
> 
> Since its the one sitting in the expo convertor (right?), I would just 
> have changed the value of that 100p cap. 100p might just be somewhat on 
> the low side. I prefer 1n in this spot.

On second thought, maybe its not the servo amp, but the input summer. 
With a gain less than one, you've probably used up all available phase 
margin, and the tempco might even be somewhat inductive. Reducing the 
noise gain would be in order to make that one stable. I.e. a 2k resistor 
from -input to GND. (With maybe a small cap in series.)

Cheers,
  René

-- 
uzs159 at uni-bonn.de
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