Is it true, that with lumped components (R, L, C) it is easier to avoid unwanted frequency of oscillation?
I am observing that distributed elements (microstrip lines, stubs) tend to repeat reflection coefficient angle over a frequency range. This results in a phase matching oscillation criteria at multiple frequencies.
In other words, when we use microstrip lines, there are many cases where load or source reflection coefficient goes from 0 to 360 deg multiple times at range 0...20GHz, but with lumped elements i do not observe such thing.