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The Y factor of an amplifier obtained by measuring the noise figure at the temperatures 77 K and 290 K is 2.7 db. Then the equivalent noise temperature of the amplifier is:

The Y factor of an amplifier obtained by measuring the noise figure at the temperatures 77 K and 290 K is 2.7 db. Then the equivalent noise temperature of the amplifier is: Correct Answer 170 K

The equivalent noise temperature of the amplifier is given by the relation (T1-YT2)/(Y-1). Substituting the given values in the above equation, equivalent noise temperature is 170 K.

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