Affects: Y-axis of Y-vs-X trace amplitude graphs
Y-axis trace amplitude measurements are taken on each frame as the difference between the level at a sample point for the Y-axis trace, and the level at this reference point.
This parameter can be set by specifying the time offset from the start of the sweep. It can also be set visually, using the pointing device to indicate the time on the displayed sweep for the reference point (and the sample point).
If the "Second trace ampl. ref" option is set to a negative value (e.g. -1p), then the reference level is not measured, and the sample level is taken as an absolute reading.
|Key sequence||Parameter||Initial Value|
|<Esc>SLSTR||Second trace ampl. ref||-0.1 msec|