The spectrum analyser plots amplitude against frequency, in other words it shows signals in the frequency domain. The spectrum analyser has the same trigger options as the oscilloscope.

To use the spectrum analyser click on the Spectrum icon on the PicoScope toolbar:

The zoom feature can be use to zoom magnify the frequency axis. This may be useful when looking at modulated signals.

Note the y scale of the spectrum analyser is usually scaled in dB. If you would like the scale to be in volts, then choose Spectrum options icon and change the Y scale to linear.