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Subject: RE: [emlsynth] Re: converting 1.2 volt/octave to 1 volt/octave

From: "George Mattson" <axisair@...>
Date: 2011-07-21

The 200 is basically just a bare integrator IC with a UJT, cap and diode network in the feedback loop. The center frequency and both swings are all summed together after their input resistors into the ame op amp input as the feedback network. The diode and UJT act as choppers to produce the sawtooth output from the integrator.
 
The output of the op amp goes to the 470 ohm output impedance resistor and capacitively coupled to the two outputs, which are hardwired to each other.
 
There's no current control, differentiation or exponential amplifier. So, it doesn't look like it was designed with any sort of scaling capacity in mind. 

From: emlsynth@yahoogroups.com [mailto:emlsynth@yahoogroups.com] On Behalf Of sprgroups@...
Sent: Wednesday, July 20, 2011 3:45 PM
To: emlsynth@yahoogroups.com
Subject: Re: [emlsynth] Re: converting 1.2 volt/octave to 1 volt/octave

 


> The 200 and 101 oscillators are a non-standard 1.20v/oct

Are you sure about the 200? The schematic I've seen looks
like a V/Hz oscillator. Or was there a later version of the 200
(201?)

Steve