Marker settings

The markers are vertical dotted lines, set to the same colour as their associated trace (see 'trace settings').
When the scan is running, they show their set frequency and the associated signal level in dBm. This label can be dragged vertically.

Marker 1 is the reference but the other three can be set to 'delta', i.e. to a fixed frequency offset from Marker 1. The offset 'delta' is set by clicking on a marker and dragging it. From v0.10.0, The label shows a 'delta' symbol and the frequency offset. When delta markers are set, Marker 1 switches to a solid line when it is dragged to a different frequency.

Markers dragged outside the sweep frequency range stop showing the signal level.

The markers can also be set to 'peak', in which case they will seek the peak associated with the marker's trace - the first four highest signals will be used. The peak markers will not track signals below the 'Peak Marker Detection Threshold' setting in the 'preferences' screen. From v0.10.0, when peak markers are selected the detection threshold level is shown by a labelled dotted red horizontal line, which can be dragged up and down to change the threshold. Dragging this line does not update the threshold level in 'preferences'.

The small '<' button next to M1 will move all enabled markers to the sweep start frequency. The '^' button sets them spaced through the sweep range. Markers remain on their set frequency when disabled, so (referring to the screenshot) if M2 only is needed at the start frequency it would be necessary to turn off the others before pressing the '<' button and turn it on again afterwards.

From v0.10.0 the check-box 'Presets' enables the fixed frequency markers (set in 'preferences') and the check-box 'Labels' turns the label on or off.