I thought it was right to simulate it with a single resistor, because
the only thing I knew about antennas was that they are oscillating
circuit.
No, they MAY be resonant circuits but, being passive, they cannot be
oscillating circuits.
I think maybe he meant to write "the only thing I knew about antennas was
that they are resonant circuit."
If the circuit really is oscillating, the output voltage will go crazy
as the added generator sweeps through the oscillating frequency.
In an AC analysis, the oscillator will NOT be oscillating. AC analysis
finds the DC operating point, then linearizes all nonlinear devices
(transistors and diodes) at that point. Then it looks at your circuit as a
fully passive network and see how much of the applied AC propagates through
the circuit.
In a TRANsient analysis, if you also applied a small sine-wave signal and
swept its frequency, you may or may not see interaction between the applied
signal and the oscillator's own frequency. Chances are the applied signal
would "pull" (or is it "push"?) the oscillator and force it to lock up with
the applied signal.
Andy
