Low frequency and thermal noise laboratory

Every measurement is limited by noise. Noise, especially low frequency noise, is extremely interesting and has been well-characterized in the past. You are required to read through this paper before this lab.

Objecives: measure thermal and 1/f noise, determine the Boltzmann constant, and determine the relationship between resistance and the magnitude of 1/f noise in carbon resistors.

Crucial points to address: units used for measuring noise, separating instrumental noise from the actual noise of the resistor

1. See my hand written note (until this website is updated)

5. Measure noise from 0.01 Hz to 1000 Hz and see if the frequency dependence remains same? What happens if you measure noise at 0.001 Hz? You could perform this measurement over a weekend.

6. Check the dependence of noise power as a function of the value of the resistance of the carbon resistor. Do you describe a relationship between the resistance and noise power (normalized)?

7. At higher frequencies, the noise will become independent of frequency. At these frequencies you will measure thermal noise. Measure thermal noise for various carbon resistors.

8. Using liquid nitrogen, verify the dependence of thermal noise on the temperature of carbon resistor.