Re: Different Phase Shift Oscillator

The Phantom wrote:
The usual phase shift oscillator with 3 CR sections needs a gain of 29 to
oscillate. Here is one that only needs a gain of 12:

http://www.digital.ee.eng.chula.ac.th/2102384/download/OSC.pdf

Is the author correct about the required gain?

I would recommend that you use Rf >= 12.2*R as a minimum.

How much gain would be needed if there were 4 CR sections?

By experiment, Rf>=6.27*R sustains oscillation, with perfect parts.

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