43.58.Kr Spectrum and frequency analyzers and filters; acoustical and electrical oscillographs; photoacoustic spectrometers; acoustical delay lines and resonators

A.N. Kozlova “Certain new demonstrations for the physics course” Sov. Phys. Usp. 11 274–275 (1968)
43.10.Sv, 43.38.Ja, 43.38.Kb, 43.58.Kr, 07.07.Hj (all)

PACS numbers