Ceyear 4051 Series, User Manual

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4. Operating Instruction
4.1 Function operation guide
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[Video] refers to the trigger measurement based on the video signal level; [Line] refers to the trigger
measurement based on the power frequency signal of AC power supply; [External 1] refers to the trigger
measurement based on the trigger input port signal of front panel; [External 2] refers to the trigger
measurement based on the trigger input port signal of rear panel; [RF Burst] refers to the trigger measurement
based on the signal power of RF input port; [Periodic Timer] refers to the predefined time period.
Except the timer trigger and free trigger, other trigger modes have the settings of [Trig Slope]. The 4051
Series Signal/Spectrum Analyzer can set the trigger polarity for these trigger modes respectively and the [Trig
Slope Pos Neg] menu is located in the submenu of each trigger mode. Negative polarity indicates that the
trigger event occurs when the trigger input signal level increases to the trigger level, while negative polarity
indicates that the trigger event occurs when the trigger input signal level decreases to the trigger level.
Except the free trigger, other trigger modes have the settings of trigger delay. The 4051 Series
Signal/Spectrum Analyzer can set the trigger delay for these trigger modes respectively and the [Trig Delay
ON OFF] menu is located in the submenu of each trigger mode. When the trigger delay is set as ―OFF‖ state,
the corresponding menu displays [Trig Delay ON OFF]; the Series Signal Analyzer will execute the
measurement immediately after the trigger event occurs. When the trigger delay is set as ―ON‖ state, the
corresponding menu displays [Trig Delay On Off], the Series Signal Analyzer will not execute the
measurement until a period of time after the trigger event occurs. The trigger delay time can be set with
number keys, Up/Down key or knob after the [Trig Delay ON OFF] is activated.
[Trig Holdoff] can set one time parameter, which limits the minimum time interval of occurrence of effective
trigger event. When the trigger holdoff is opened, the trigger event that occurs within the trigger holdoff time
will be neglected after one trigger event.
1) Execute video trigger measurement
The trigger input signal corresponding to the video trigger is the IF signal envelope displayed on the screen.
The external trigger level can be set in such steps of pressing the
【
Trig
】
key on the front panel, entering
[Video
▶
], pressing soft menu of [Trigger Level] and then using the number keys, Up/Down key or knob.
After entering[Video] menu, the Series Signal Analyzer will automatically execute the video trigger
measurement. By default, the vide trigger level is -25 dBm, and the display line (red) of trigger level and
trigger level value will displayed on the screen and the ―Video Trigger‖ will be displayed in corresponding
state bar, as shown in Fig. 4.2.