2007-03-21 20:24:30 · 5 answers · asked by e r 1 in Science & Mathematics ➔ Engineering
The antenna picks up all frequencies and signals in the radio spectrum. AM, FM, everything.
The circuitry of the radio filters that to the public AM radio frequency range. Then the tuning circuitry filters out all but the frequency selected by the tuning control.
This signal is then demodulated by other circuitry into an audio signal which is amplified for the speakers.
2007-03-21 20:36:12 · answer #1 · answered by Just Helping 4 · 0⤊ 0⤋
As stated above, an Antenna will actualy recieve pretty much everything, but the length of said antenna will be a direct proportion of the wavelength of the signal you are trying to recieve, i.e. 1/4 of the wavelength etc, this makes the gain of the antenna greater at the correct frequency. There are various stages in an RF reciever, a filter which is tuned to the exact frequency you need, a demmodulator which separates the audio component from the RF carrier. Hope this has helped !!!
2007-03-21 21:55:44 · answer #2 · answered by Ian B 2 · 0⤊ 0⤋
AM stands for amplitude modulation. Therefore, the signal that reaches the receiver is a simple sine/cosine wave whose amplitudes follow the message signal that is being transmitted across space.
2007-03-21 20:30:57 · answer #3 · answered by Imperial 2 · 0⤊ 0⤋
if I give you a sine wave how would you use it to send a message?
1 . you vary the amplitude , Amplitude Modulation (AM) or
2. you vary the frequency , Frequency Modulation (FM)
So the answer to your question is amplitude modulated signal.
2007-03-21 20:31:39 · answer #4 · answered by 987654321abc 5 · 0⤊ 0⤋
an audio modulated signal.
2007-03-21 20:29:23 · answer #5 · answered by R.E.M.E. 5 · 0⤊ 0⤋