This section gives some samples of pictorial and acoustic represented dynamic spectra. The spectrograms at the left show the channels with radio frequency increasing upward. It also agrees with musical notation, where lower pitch is drawn in lower positions. For coherent solar radio bursts emitted on characteristic frequencies of the local plasma frequency, this representation means that structures moving downward in frequency and in the spectrogram propagate to higher altitude in the solar corona. Clicking on the pictures on the left gives a larger view of the spectrograms.
Patches drifting to higher frequencies are clearly audible.
They indicate radio sources moving to higher density and thus presumably downward in the solar corona. A threshold at 122 sfu above background is subtracted. The frequency mapping is tempered pentatonic and the note duration is 0.1 s. Clearly audible reverse drifting type III -like structures, especially in the second part of the sample. Such bursts are interpreted by electron beams accelerated in the corona and moving toward lower altitudes. This is an example, where the acoustic representation reveals the structures more clearly than the pictorial representation.