The mixing occurs in the base emitter junction diode.
To produce the full output waveform the 1k collector resistor can be replaced with a parallel tuned circuit set to 470 Khz. The back emf of the inductor provides the mirror image of the waveform.
I could not adjust the time base in every circuit enough to show this. The output impedance of the transistor at Ic = 10 mA will be about 10K. This value can be used to set the parallel Q factor in the resonant tank load.
