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Explain Superhetrodyne Receiver
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The features of hetrodyne receiver is that all incoming radio frequency signals are converted into a fixed frequency signal called intermediate frequency by using hetrodyne process.

In this receiver, the received signal frequency is mixed with the local oscillator frequency fo. The local oscillator is an LC oscillator which produce sinusoidal oscillations of frequency $F_o$ The frequency of local oscillator depends on the values of L & C of associated tuned cut. The signal frequency $f_s$ & signal $f_0$ given to the mixer ckt, mixer is a non linear ckt, it will produce the output which contain different frequency component such as $f_s, f_0, f_0 + f_s$ harmonics of input frequencies and the IC components, the input tank ckt of IF amplifier is tuned to $f_o - f_s$ which is always 455KHz and is known as intermediate frequency If. To get If always = 455KHz, the local oscillator should be tuned such that whatever may be input signal frequency $f_s$, local oscillator frequency fo should be always 455KHz, more than $f_s$ AM wave with 455 KHz is amplified to the desired level by 2 or 3, if amplifier and then it is fed to the detector which detects a taken out the AF information from the AM wave.

This audio frequency signal is then amplified by voltage and power so that it can drive the load speaker.

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