Purpose of this instrument is to find numerically the Fourier
components (both their moduli and phases) of a curve given in
drawing. To accomplish this, one needs both the analyzer proper (large box, long side 60 cm)
and a polar planimeter (foreground box) driven by the output of the
analyzer. The instrument was designed by Otto Mader and built by
Gebrüder Stärzl, München 1909. The principle of the harmonic analyzer has first been described by William Thomson (Lord Kelvin) in his Treatise on Natural Philosophy (1879).
This manual (7.4 MB pdf) contains a full description of the instrument's workings.
View of the analyzer set-up, taken from the manual.
The analyzer and the accompanying pole planimeter were
donated by the VanderWaals-Zeeman physics laboratory of the
University of Amsterdam.
