Problem 8 Consider a superheterodyne receiver for standard AM radio. a. Sketch a block diagram of the superheterodyne receiver showing the major blocks. b. If you wish to receive a radio station at 1600 ���, what local oscillator frequency is needed? (Let ��� = 455 ���) c. What is the “image station” we need to watch out for using this local oscillator frequency? d. Sketch example spectra to illustrate how the local oscillator effectively shifts a transmitted signal spectrum centered at 1600 ��� to on that is centered at 455 ���.