Would you be able to hear the carrier wave of an amplitude modulated station, if you could hear in the MHz range, or would the high frequency be filtered out after rectification?
2 Answers
If you could hear audio in the MHz range, you still couldn't hear the carrier.
Speakers don't work up to those ranges. You would need something like an ultrasound transducer.
The AM or medium wave band extends from 526.5 kHz to 1606.5 kHz in Europe or 535 kHz to 1705 kHz in the US.
Ultrasound (not supersound! :-) frequencies range from 20kHz and up:
However, a bigger problem is that AM stations broadcast using electromagnetic radiation, whereas sound travels by acoustic waves in the air.
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1$\begingroup$ If you could hear electromagnetic radiation in that frequency range, you would be able to hear the carrier since its existence is key to the demodulation of AM radio (at least back then). If you know how AM (DSB-AM) is generated (multiplying a carrier of the right frequency with an audio signal, thereby convolving it in the frequency domain - You might want to read up on that) it will become clear that the carrier is always there and audible, unless you employ a demodulator or use DSBSC. $\endgroup$ Jun 29, 2016 at 16:32
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$\begingroup$ But I know you can't hear electromagnetic radiation, I was asking if you could hear it after it has gone through the speaker in the reciever $\endgroup$ Jun 29, 2016 at 16:36
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$\begingroup$ Yes, you could. Just leave the demodulator out of the signal chain and you will be able to hear it. $\endgroup$ Jun 29, 2016 at 16:52