Communication Systems - Engineering

Q1:

An amplifier operating over a frequency range of 18 to 20 MHz has 10 kΩ input resistance. At a temperature of 27° C, the noise voltage at input of amplifier is (Boltzman constant k = 1.38 x 10-23 J/K)

A 18.2 μV

B 182 μV

C 16.2 μV

D 162 μV

ANS:A - 18.2 μV

Using Equation Va = (4 x 1.38 x 10-23 x 300 x 2 x 106 x 104)0.5 = 18.2 x 10-6 V.