The goal of this question. Demodulate the AM signal.
(Please assume a diode demodulating AM radio of the most imaginable simplicity.)
I am assuming an alternating current sine wave is coming into a wire from the antenna? In order for an envelope to coexist with the sine wave the amplitude is varying I assume?
If the antenna is the correct length then resonance of some fundamental frequency of the EM wave allows the signal to increase in strength in the antenna before it enters the diode? An assumption on my part.
The signal is then converted to DC but since the strength of the signal determines the fluctuations in the "envelope" the voice information is in "duplicate" so the bottom half is cut out of the rectifier , no? From this point I am lost.
The sketch shows a capacitor in parallel. I know what a capacitor does in principle. Is it attempting to maintain the voltage as the current changes since capacitors don't like to have their voltage changed and resist it, no? Please complete my picture to demodulate the AM signal.