Yale University

PHYS 381/504: Op. amps., quartz resonators, and noise

Introduction
Johnson Noise
Macroscopic Derivation
Microscopic Derivation
Install and Test the Optical Amplifier
Install the Tuning Fork
Welcome to LabView
Tune out the Package Capacitance
Gather Data
Load the Driven Circuit Data
Fit the Driven Circuit Data
Find Circuit Characteristics from this Fit
Analyze the Undriven Circuit from Characteristics
Final Results
References
-------------------------------------------------------
PHYS 381La HOME
Classes Page
Yale Graduate School
Yale University

Andrew Pariser, December 2005
modified S.M., January 2006

© 2006 Yale University, New Haven, Connecticut 06520

Data Gathering

Turn off the white noise source.

Run the LabView vi. You should still be able to find your resonance peak. It may, however, be buried in more noise than originally expected.

Turn OFF any nearby unnecessary electrical equipment (an Oscilloscope has a nice operating frequency of 44 kHz which looks great in the results). Doing so may help mitigate extraneous noise.

Consider low frequency values, and observe a peak at 60 Hz (as well as at many of its harmonics). This is the frequency of the line voltage in the room. Also, observe the 1/f noise.

Top