Describe the functions of mixer and local oscillator in radio receiver

Describe the functions of mixer and local oscillator in radio receiver
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1 Answer

Answer :

Frequency Mixer:- The function of frequency mixer is to heterodyne signal frequency fs and local oscillator frequency fo. At the output, it produces the difference frequency known as intermediate frequency fi. (practical value of IF is 10.7MHz ) for FM and 455KHz for FM

Local oscillator:- Since FM broadcast operates in VHF and UHF band, a separate local oscillator is used in FM receiver .The local oscillator frequency fo is then mixed with incoming frequency to give intermediate frequency. 
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