74 Keysight InfiniiVision 2000 X-Series Oscilloscopes User's Guide
4 Math Waveforms
A scale unit of U (undefined) will be displayed for math functions when two source
channels are used and they are set to dissimilar units and the combination of units
cannot be resolved.
Math Operators
Math operators perform arithmetic operations (add, subtract, or multiply) on
analog input channels.
• “Add or Subtract" on page 74
• “Multiply or Divide" on page 75
Add or Subtract
When you select add or subtract, the Source 1 and Source 2 values are added or
subtracted point by point, and the result is displayed.
You can use subtract to make a differential measurement or to compare two
waveforms.
If your waveforms' DC offsets are larger than the dynamic range of the
oscilloscope's input channels you will need to use a differential probe instead.
* When the FFT source is channel 1, 2, 3 or 4, FFT units will be displayed in dBV when channel units
is set to Volts and channel impedance is set to 1 M
Ω. FFT units will be displayed in dBm when
channel units is set to Volts and channel impedance is set to 50
Ω. FFT units will be displayed as dB
for all other FFT sources or when a source channel's units has been set to Amps.
Math function Units