|Oscillations and Waves > Instruments > Air Columns||DCS# 3D30.40|
Sweep through the frequencies of the function generator and listen for the resonant frequency of the spherical cavity. Use a microphone and oscilloscope to show the change in amplitude.
Helmholtz resonators were an early version of the spectrum analyzer: to identify frequency components in a given note, place one end of the resonator of the frequency of interest to your ear and listen for that frequency in the note.
Tom Greenslade's early physics apparatus pages: