User manual

Triggers
R&S
®
RTO
62User Manual 1316.0827.02 ─ 06
Fig. 3-2: Standard width trigger
ThrRising = ThrFalling = Trigger thresholds for rising and falling edge are the same. The instrument misses
the falling edge at T=0,27 because the signal stays below the hysteresis threshold.
No trigger occurs.
The robust trigger inserts a shift by the hysteresis value between the trigger threshold for
the falling edge and the trigger threshold for the rising edge. Thus, the trigger cannot
"hang" inside the hysteresis, triggering is always ensured.
Fig. 3-3: Robust width trigger
ThrRising = HystFalling, ThrFalling = HystRising = Rising and falling edge are detected by turns, noise is
rejected, less accuracy in trigger measurement
The disadvantage of the robust trigger is a slight inaccuracy in the trigger measurements,
because different trigger levels are used. For steep edges, the inaccuracy can be ignored.
See also: chapter 3.3.3, "Noise Reject", on page 79
SCPI command:
TRIGger<m>:ROBust on page 456
3.3.1.2 Edge
The edge trigger is the most common trigger type. It is well-known from analog oscillo-
scopes; and you can use it for analog and digital signals.
The trigger event occurs when the signal from the trigger source passes the specified
threshold voltage in the specified direction (slope).
Reference for Triggers