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Waterfall

A waterfall shows a spectrum over time: one axis represents frequency, the other time. Colour represents relative signal level.

Also found under: Waterfall · Wasserfall · Spektrogramm · Spectrogram

A concrete example

A continuous narrow carrier draws a line; a brief pulse leaves only a short trace.

What to keep in mind

Bright colours do not prove a particular received power without a calibrated scale.

Further reference

Original explanation based on the technical documentation. Reviewed on 15 October 2026.

Marc Lichtman · PySDR: Frequency Domain ↗