Re: Different Phase Shift Oscillator


"The Phantom"
"Phil Allison"

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?



** The link does not say what you claim.

Then let me put it this way. Is the author correct that the criterion
for oscillation is RF > 12R?


** Probably.

But the link does not say what YOU claimed.



And if another CR section is added, what will
be the criterion for oscillation?


** RF will need to be bigger.

Go find a site that has the WHOLE story about such oscillators.

Cos that one is crap.





......... Phil




.

Relevant Pages

  • Re: Homebrew AM transistor radio
    ... >> Each amplifier stage should have a series resistor of 100 ohms and a bypass ... >> every 40dB of gain. ... The gain attainable before oscillation ... remaining is the out of phase feedback to the base via a capacitor ...
    (rec.radio.amateur.homebrew)
  • Re: A definition please - relaxation oscillations
    ... oscillation signal "burns up" excited atoms and pulls gain down (aka ... Steady-state oscillation requires signal level to be ... solid state lasers); and again v.v. ...
    (sci.optics)
  • Re: HiWatt DR504 phase splitter problem
    ... pushing the output tube grids into conduction. ... A 12AT7 would have about the same gain as the 12AX7 in that circuit ... causing oscillation, I've seen that symptom before and that was the ... doesn't explain the problems with the sound. ...
    (alt.guitar.amps)
  • Re: Looking to modify this circuit for 30Hz operation
    ... can tell it's a Wein Bridge with the two LEDs serving the function ... R6 and C1/C2 and the frequency of oscillation? ... the gain must equal exactly 3. ...
    (sci.electronics.basics)
  • Re: more speakers - more sound
    ... >>> Push the gain up in a quiet room and many modes will be ... there is no threshold. ... As for "feedback threshold" a better descriptor ... the oscillation progression is linear but the ...
    (rec.audio.pro)