1-20
IM 253710-01E
• Auto mode
If a trigger occurs within a specified amount of time (about 100 ms, referred to as
the timeout period), the waveform display is updated. If the trigger does not occur
within the timeout period, the waveform display is automatically updated.
• Auto-level mode
If a trigger occurs within the timeout period, the waveform is displayed in the same
way as in the auto mode. If a trigger does not occur within the timeout period, the
center value of the amplitude of the trigger source is detected, the trigger level is
automatically changed to the center value, and the trigger is generated to update
the displayed waveform.
1/2 of the amplitude
1/2 of the amplitude
Trigger level
Amplitude
• Normal mode
The waveform display is updated only when the trigger occurs. If a trigger does not
occur, the display is not updated.
• HF auto mode
The output of the zero crossing detector of the trigger source is used to detect the
trigger condition. When the zero crossing filter is set, the trigger becomes less
susceptive to harmonic noise and unexpected triggers are prevented from
occurring. Because the trigger occurs when the input signal crosses the center
level of the amplitude of the trigger source (a hysteresis of approx. 3.5% of the
measurement range exists) and the display is updated, the trigger level setting is
void.
• HF normal mode
The method in which the trigger is activated is the same as in the HF auto mode.
The behavior with respect to the timeout period is the same as in the normal mode.
1.4 Trigger