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ENTC 4350. HOMEWORK SET 3 Chapter 5. Chapter 5, Problem 4. Calculate the noise voltage between dc and 1000 Hz due to thermal agitation in a circuit containing only a 75- W resistor. Chapter 5, Problem 6.
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ENTC 4350 HOMEWORK SET 3 Chapter 5
Chapter 5, Problem 4. • Calculate the noise voltage between dc and 1000 Hz due to thermal agitation in a circuit containing only a 75-W resistor.
Chapter 5, Problem 6. • What is the shot-noise level over the bandwidth dc to 20 kHz in a conductor in which 100 mA flows?
Chapter 5, Problem 7. • Two noise sources are present in a circuit: a voltage source that produces 50 mV (rms), and a current source in which a 120 nA current flows in a 100-W resistance. What is the average noise voltage of this circuit?
Chapter 5, Problem 8. • A circuit has a noise figure of 4.7 dB. Calculate the noise factor.
Chapter 5, Problem 10. • Three amplifiers in cascade have the following characteristics: • Calculate the noise factor for the entire chain.
Chapter 5, Problem 10. Convert the noise figures into noise factors: Use Friis’s equation:
Chapter 5, Problem 10. Use Friis’s equation:
Chapter 5, Problem 11. • Reverse the order of the amplifiers in problem 10 (i.e. exchange A1 and A3), and recalculate the noise factor. Compare the results.
Chapter 5, Problem 11. Use Friis’s equation:
Chapter 5, Problem 12. • An op-amp has an open-loop gain of 1,000,000. Calculate the closed loop gain when b = 0.10.
Chapter 5, Problem 13. • An EEG signal processes a 10 mV signal in the presence of 125 mV of random noise. Calculate the processing gain and processed SNR if signal averaging of 256 repetitions of the waveform is performed.