A basic lock-in amplifier experiment for the undergraduate laboratory
- 13 October 2003
- journal article
- Published by American Association of Physics Teachers (AAPT) in American Journal of Physics
- Vol. 71 (11) , 1208-1213
- https://doi.org/10.1119/1.1579497
Abstract
We describe a basic experiment for the undergraduate laboratory that demonstrates aspects of both the science and the art of precision electronic measurements. The essence of the experiment is to measure the resistance of a small length of brass wire to high accuracy using a simple voltage divider and a lock-in amplifier. By performing the measurement at different frequencies and different drive currents, one observes various random noise sources and systematic measurement effects.This publication has 3 references indexed in Scilit:
- The mathematics of Brownian motion and Johnson noiseAmerican Journal of Physics, 1996
- Fluctuation and dissipation in Brownian motionAmerican Journal of Physics, 1993
- The lock-in amplifier: A student experimentAmerican Journal of Physics, 1991