@MangaFanX:
And here a little experiment:
Extracted the 7.8Hz component with a low Q bandpass filter (Q=2) and modulated the VCO port of
a function generator chip (XR2206), carrier frequency ~ 615Hz. This makes the otherwise sub -
audible 7.8Hz Schumann resonance audible by "warbling" the 615Hz carrier. Unfortunately there
are also occasionally high level transients (noise spikes), and these cause a sudden ,large frequen-
cy displacement with some ringing. The .wav file is ~ 340kB long, the last 5 seconds of the 30 secs.
recording have (for comparison) the signal modulation switched off
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na ja, so ungefähr hört sich die 8hz frequenz eben an.