Hello, I'm having trouble understanding a very fundamental question with respect to RF measurements.
This I know:
Rollett stability factor (K): determines if a transistor will oscillate due to input and output impedance conditions present at the ports of a transistor. (i.e. if K>1 & |delta| = |(S11)(S22)-(S12)(S21)| 1 to where MAG=1 to find Fmax.
This is where I'm confused.
If one is measuring MAG in a region where K>1 then by definition the transistor is NOT oscillating and thus how can we determine the MAXIMUM oscillation frequency if the transistor is not oscillating in that region already??????
Also why is the maximum oscillation frequency (Fmax) defined as the frequency for which the power gain = 1 (input power = output power)??
What is the correlation??
Thanks for the help