jasmin_123
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Could somebody give an INTUITIVE(!) explanation why a loop-gain greater
than one does not necessarily causes instability?
My professor has promised a 30-point bonus in the exam for this answer.
I spent almost all the time before the exam to find any hint on the net and in books
with NO success. Help, please!
---
I am talking about positive feedback oscillators and the Barkhausen oscillation criterion.
It is implied that AOL*B is REAL, POSITIVE, and greater than one, and this does not always mean that the oscillator is unstable. It can be stable.
Again, an INTUTIVE explanation is needed, without Nyquist, root locus, and so on.
Feb 12
Well, guys, I felt that we started to make circles and asked the tutor for a hint (at the expense of the 10 bonus points, too bad).
---
The hint was as follows:
"The loop-gain greater than one, at a frequency where the phase is zero, provides no more information about oscillator stability than the color of the oscillator capacitors does!"
Does it say anything to you???
than one does not necessarily causes instability?
My professor has promised a 30-point bonus in the exam for this answer.
I spent almost all the time before the exam to find any hint on the net and in books
with NO success. Help, please!
---
I am talking about positive feedback oscillators and the Barkhausen oscillation criterion.
It is implied that AOL*B is REAL, POSITIVE, and greater than one, and this does not always mean that the oscillator is unstable. It can be stable.
Again, an INTUTIVE explanation is needed, without Nyquist, root locus, and so on.
Feb 12
Well, guys, I felt that we started to make circles and asked the tutor for a hint (at the expense of the 10 bonus points, too bad).
---
The hint was as follows:
"The loop-gain greater than one, at a frequency where the phase is zero, provides no more information about oscillator stability than the color of the oscillator capacitors does!"
Does it say anything to you???