The title is a bit old fashioned German, in contemporary German it would say "Frequenzen und Amplituden der Harmonischen einer Sägezahnwelle" which translates to "Frequencies and Amplitudes of the harmonics of a sawtooth wave". The spoken word is exactly that, they read out the number of each harmonic and its relative amplitude. The morse code in the background is the same, just the numbers played out as morse. All sounds and modulators are only plain sawtooth waves, filtered and delayed and with different envelopes, at most one each in order not to lose the acoustic quality of the sawtooth wave