What does the detector do in a radio receiver?

What does the detector do in a radio receiver?

• A. Separates the audio information from the carrier wave
• B. Amplifies the RF signal
• C. Mixes signals from the local oscillator
• D. Converts audio to digital

Answer: (A)

In AM reception, the detector’s job is to demodulate the signal and recover the original audio. The incoming AM signal carries the audio information in the varying envelope of the carrier. The detector (often a diode with an RC filter) removes the high-frequency carrier and leaves a voltage that follows that envelope. That low-frequency audio voltage is what the audio amplifier and speaker use. So the detector’s role is to separate the audio information from the carrier wave, turning the modulated RF signal back into the sound you can hear. It doesn’t amplify the RF itself, which is done by the RF stage, it doesn’t mix with a local oscillator, and it doesn’t convert the signal to digital—that would be later processing after demodulation.

In AM reception, the detector’s job is to demodulate the signal and recover the original audio. The incoming AM signal carries the audio information in the varying envelope of the carrier. The detector (often a diode with an RC filter) removes the high-frequency carrier and leaves a voltage that follows that envelope. That low-frequency audio voltage is what the audio amplifier and speaker use.

So the detector’s role is to separate the audio information from the carrier wave, turning the modulated RF signal back into the sound you can hear. It doesn’t amplify the RF itself, which is done by the RF stage, it doesn’t mix with a local oscillator, and it doesn’t convert the signal to digital—that would be later processing after demodulation.