A superheterodyne radio receiver with an IF of 455KHZ is turned to 1000KHZ. Find: (i) Image frequency (ii) Local oscillator frequency

A superheterodyne radio receiver with an IF of 455KHZ is turned to 1000KHZ. Find: (i) Image frequency (ii) Local oscillator frequency
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1 Answer

Answer :

Given Intermediate Frequency fi=455KHz

Signal frequency =fs=1000KHz

Local oscillator frequency fo=fs+fi

 Fo=1000KHz+455KHz

 =1455KHz

Image frequency is the input frequency which produces the same intermediate frequency

fsi=fs+2fi

 =1000KHz+2*455KHz

 =1910KHz 
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