Rigol DG800 Series, Руководство пользователя

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Chapter 2 Front Panel Operations RIGOL
DG800 User's Guide 2-61
3. Manual Trigger
In the Manual trigger, when you press Trig on the front panel for one time, one
sweep is immediately launched for the corresponding channel.
Key Points:
When "External" trigger is selected, tap the Trig In to select "RisEdge" or
"FallEdge". The rear-panel [CH1/Sync/Ext Mod/Trig/FSK] connector is used
as the input terminal of the external trigger signal. When "RisEdge" is selected, the
instrument triggers one sweep at the rising edge of the input signal. When
"FallEdge" is selected, the instrument triggers one sweep at the falling edge of the
input signal.
Marker Freq
The sync signal output from the rear-panel [CH1/Sync/Ext Mod/Trig/FSK]
connector that corresponds to the channel on the front panel always changes from
low level to high level at the start of each sweep. When the "Marker" function is
disabled, the sync signal will change to low level at the center frequency point. When
the "Marker" function is enabled, the sync signal changes to low level at the specified
marker frequency point.
After the sweep function is enabled, tap the Marker menu label to select "On". Then
tap the Marker Freq menu label, and use the numeric keypad to modify the marker
frequency. You can also use the arrow keys and the knob to modify the marker
frequency. The default value is 550 Hz, and the available range is limited by "Start
Frequency" and "Stop Frequency".
The generator will restart to sweep and output from the specified "Start Frequency"
after the mark frequency is modified.
Key Points:
For step sweep (the sweep points determined by the start frequency, stop
frequency, and step respectively are f
1
, f
2
, ……, f
n
, f
n+1
……), if the marker frequency
setting is one of the sweep points values, the sync signal is TTL high level at the
start of the sweep and will change to low level at the marker frequency point. If the
set marker frequency is not equal to the value at the sweep point, the sync signal
will change to low level at the sweep point which is closest to this marker
frequency.