Agilent Technologies E4406A manual Trigger Source

Making Measurements

Preparing for Measurements

Trigger Source

Changing the Trig Source alters the trigger source for the current measurement only. Not all of the selections are available for all measurements. Note that the RF Burst, Video, Ext Front, and Ext Rear menu keys found in the Trigger menu enable you to change settings to modify the delay, level, and slope for each of these trigger sources (as described on page 85. Choose one of the following trigger sources:

•Free Run - Triggers at the time the data is requested, completely asynchronous to the RF or IF signals.

•Video - Is an internal IF envelope trigger. It triggers on an absolute threshold level of the signal passed by the IF.

•RF Burst - Is an internal wideband RF burst trigger that has an automatic level control for burst signals.

•Ext Front - Activates the front panel Ext Trigger Input. The external trigger must be a signal between −5 and +5 volts.

•Ext Rear - Activates the rear panel Trigger In. The external trigger must be a signal between −5 and +5 volts.

•Frame - Uses the internal frame clock to generate a trigger signal. The clock parameters are controlled under the Mode Setup key or the measurement firmware, not both. See the specific measurement for details.

•Line - Activates an internal line trigger. Sweep triggers occur at intervals synchronized to the line frequency.

Rear panel TRIGGER 1 OUT and TRIGGER 2 OUT connectors are coupled to the selected trigger source. These trigger outputs are always on the rising edge with a pulse width of at least 1 ∝s.

92 Chapter 4