What frequency does the Local Oscillator (LO) operate above the original RF signal in an AM receiver?

What frequency does the Local Oscillator (LO) operate above the original RF signal in an AM receiver?

• A. 500 kHz
• B. 455 kHz
• C. 1 MHz
• D. 2.4 GHz

Answer: (B)

In an AM (Amplitude Modulation) receiver, the Local Oscillator (LO) typically operates at a fixed frequency above the frequency of the original RF (Radio Frequency) signal to produce an intermediate frequency (IF) signal. The standard intermediate frequency used in traditional AM receivers is commonly set at 455 kHz. The purpose of this frequency difference is to allow for easier filtering and amplification of the desired signal while reducing potential interference from other signals. By mixing the incoming RF signal with the LO frequency, the receiver generates an IF signal at 455 kHz, which is easier to process. This practice is integral to the design of AM receivers, which helps with demodulation, ensuring clearer sound and better selectivity in terms of tuning into specific stations. Hence, the operation of the Local Oscillator at 455 kHz above the RF signal is a standard practice in AM receiver design.

In an AM (Amplitude Modulation) receiver, the Local Oscillator (LO) typically operates at a fixed frequency above the frequency of the original RF (Radio Frequency) signal to produce an intermediate frequency (IF) signal. The standard intermediate frequency used in traditional AM receivers is commonly set at 455 kHz.

The purpose of this frequency difference is to allow for easier filtering and amplification of the desired signal while reducing potential interference from other signals. By mixing the incoming RF signal with the LO frequency, the receiver generates an IF signal at 455 kHz, which is easier to process.

This practice is integral to the design of AM receivers, which helps with demodulation, ensuring clearer sound and better selectivity in terms of tuning into specific stations. Hence, the operation of the Local Oscillator at 455 kHz above the RF signal is a standard practice in AM receiver design.