Spectrum plot
To zoom in and out the horizontal (i.e. frequency) axis, place the mouse pointer over the spectrum and roll the mouse wheel.
Selected interval plot
To zoom in and out the horizontal (i.e. time) axis of the Selected interval plot, do one of the following:
nEnter the length of the Time interval you require.
nPlace the mouse pointer somewhere over the plot area (see the second plot in the figure below), then roll the mouse wheel. Note that the zoom is centered on the current position of the mouse pointer.
Spectrogram
To zoom in/out the time axis:
nAdjust the value of Time interval at the top of the screen, or
nPlace the mouse pointer somewhere over the spectrogram area (see the figure below), then roll the mouse wheel. Note that the zoom is centered on the current position of the mouse pointer.
To zoom in/out the frequency axis:
nPlace the mouse pointer somewhere over the spectrogram area (see the figure below), then hold Ctrl down and roll the mouse wheel. Note that the zoom is centered on the current position of the mouse pointer.
nAlternatively, right-click the spectrogram area and under Frequency scale adjust the values Min frequency and Max frequency. Check the spectrogram on the background. When you are happy with the zoom level, click OK.
With the Auto options near Min frequency and Max frequency you return to the default range determined by the microphone sample rate.