Re: Different Phase Shift Oscillator


"The Phantom" <phantom@xxxxxxx> wrote in message
news:jg2gi3lee1e8ofqipmr3stiss9781qhlp1@xxxxxxxxxx
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?

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


How do you get 29? For a single RC network the loss at 60 degrees is about
2. So, you would need a gain of 2**3=8.

Tam


.

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