Trigger level mode

The Trigger level mode defines how the trigger level is set. Trigger level mode can be set to one of two values:

  • Relative: the trigger level is set as a percentage of the full scale input range
  • Absolute: the trigger level is set as an absolute voltage value, independent of the input range.

Trigger level mode is a channel setting, it can be set for each channel individually. Trigger level mode is set to Absolute by default.

Absolute trigger level

When Trigger level mode is set to Absolute, the trigger level is set as an absolute voltage value, independent of the input range. When the input range changes, either by setting it to a different range, or by auto ranging because the input signal changes, the trigger level will remain at the same absolute voltage level. When the trigger level is set to a value outside the current input range, the input range will be increased to make the trigger level fit. The input range cannot be set to a lower value than the currently set trigger level.

Relative trigger level

When Trigger level mode is set to Relative, the trigger level is set as a percentage of the full scale input range:

  • 100 % corresponds to a trigger level at positive full scale of the input range,
  • 50 % corresponds to a trigger level at 0 V,
  • 0 % corresponds to a trigger level at negative full scale of the input range.

When the input range changes, either by setting it to a different range, or by auto ranging because the input signal changes, the trigger level will remain at the same percentage of the full scale input range. This means that the voltage at which the trigger level is set will change.

Setting the trigger level mode

Setting the trigger level mode can be done by right-clicking the instrument in the Object tree and then selecting Trigger level mode and the required value from the popup menu.