User manual

WaveSurfer 3000 Oscilloscopes
Interval Trigger
Interval triggers upon finding a specific interval, the time (period) between two consecutive edges of the
same polarity: positive to positive or negative to negative. Use the interval trigger to capture intervals that
fall short of, or exceed, a specified range.
On the Trigger dialog, select Smart trigger type, then Interval to display the controls.
ANALOG INTERVAL
1. Choose the Source input.
2. Choose the type of signal Coupling at the input. Choices are:
l DC - All the signal’s frequency components are coupled to the trigger circuit for high frequency
bursts or where the use of AC coupling would shift the effective trigger level.
l AC - The signal is capacitively coupled. DC levels are rejected, and frequencies below 10 Hz are
attenuated.
l LFREJ - The signal is coupled through a capacitive high-pass filter network, DC is rejected and
signal frequencies below 400 kHz are attenuated. For stable triggering on medium to high
frequency signals.
l HFREJ - Signals are DC coupled to the trigger circuit, and a low-pass filter network attenuates
frequencies above 1 MHz (used for triggering on low frequencies).
3. Choose the Slope (edge) from which to measure.
4. Enter the voltage Level at which to measure interval width. Where available, the Find Level button sets
the level to the signal mean.
5. Use Interval Condition is settings to create an expression describing the triggering interval. This may be:
l Any width Less Than an Upper Value.
l Any width Greater Than a Lower Value.
l Any width In Range or Out Range of values. You may describe the range using either:
l Limits, an absolute Upper Value and Lower Value.
l Delta, any Nominal width plus or minus a Delta width.
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