The front-end of a television receiver, having a bandwidth of 7Mhz, and operating at a temperature of 27˚C , consists of an amplifier having a gain of 15 followed by a mixer whose gain is 20. The amplifier has a 300 Ω input resistor and a shot noise equivalent resistance of 500Ω; for the mixer, these values are 2.2kΩ and 13.5kΩ respectively, and the load resistance of the mixer is 470 kΩ. Calculate the equivalent noise resistance for this television receiver. A. 8760 Ω B. 875Ω C. 8.76Ω D. 0.876Ω

The front-end of a television receiver, having a bandwidth of 7Mhz, and operating at a
temperature of 27˚C , consists of an amplifier having a gain of 15 followed by a mixer
whose gain is 20. The amplifier has a 300 Ω input resistor and a shot noise equivalent
resistance of 500Ω; for the mixer, these values are 2.2kΩ and 13.5kΩ respectively, and
the load resistance of the mixer is 470 kΩ. Calculate the equivalent noise resistance for
this television receiver.
A. 8760 Ω
B. 875Ω
C. 8.76Ω
D. 0.876Ω
by

1 Answer

Answer :

B. 875Ω
by

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