FUNCTION REFERENCE

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SUBTRACT (MATHEMATICS)

The subtract mode is available in the digital mode of operation.

Description:

The SUBTRACT function performs a point-to-point subtraction of two traces. Each point related to the respective ground levels (indicated as ‘-’). The result of the SUBTRACT function is a new trace in a different register. This trace can be scaled and positioned.

Scaling is the correction of the resultant trace to fit in the screen. Scaling can be adjusted by using the TRACK control.

Vertical positioning is called offset. It offsets each sample in the resultant trace with a certain value so that the trace can be "moved" vertically. It is adjusted with the Δ control.

The scale factor and the offset factor are displayed in the ‘MATH SCALE’ menu. Pressing the ‘autoscale’ softkey automatically selects the settings for the trace to fit the screen.

When subtracting signals with different amplitude settings, the size of the smaller signal is automatically adjusted to match the size of the larger signal.

Newly acquired traces or previously stored traces can be used as the source for this process and can be selected with the Δ control. The resulting trace is automatically written in a register memory (m1 for math1 or m2 for math2).

To see the result more clearly, you can turn off the two source traces by pressing the ‘DISPLAY SOURCE on/off softkey’.

Mathematical description:

Result = S1 - S2

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Fluke PM3370B user manual Subtract Mathematics, Subtract mode is available in the digital mode of operation, Result = S1 S2