Rigol DG811, Руководство пользователя

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Chapter 2 Front Panel Operations RIGOL
DG800 User's Guide 2-39
To Select Modulation Source
DG800 can receive modulating waveform from the internal or external modulation
source. Tap the Source parameter selection field to select an "Internal" or "External"
modulation source.
1. Internal Source
When internal modulation source is selected, tap the Mod.Wave parameter
selection field to select Sine, Square, Triangle, UpRamp, DnRamp, Noise, or Arb
as modulating waveform. By default, Sine is selected.

Square: 50% duty cycle.

Triangle: 50% symmetry.

UpRamp: 100% symmetry.

DnRamp: 0% symmetry.

Arb: the arbitrary waveform selected for the current channel.
Note: Noise can be used as the modulating waveform but cannot be used as
carrier waveform.
2. External Source
When the external modulation source is selected, Mod.Wave and Mod.Freq
will be grayed out and disabled. The generator receives the external modulating
signal from the rear-panel [CH1/Sync/Ext Mod/Trig/FSK] connector. At this
time, the frequency deviation of the modulated waveform is controlled by the ±5
V signal level of the connector. For example, if the frequency deviation is set to 1
kHz, +5 V signal level corresponds to a 1 kHz increase in frequency and -5 V
signal level corresponds to a 1 kHz decrease in frequency.
To Set Modulating Waveform Frequency
When the internal modulation source is selected, tap the Mod.Freq parameter input
field and use the numeric keypad to set the modulating waveform frequency.

You can also use the arrow keys and the knob to input a desired frequency
value.

The modulating waveform frequency ranges from 2 mHz to 1 MHz, and the
default value is 100 Hz.
Note: When the external modulation source is selected, this menu will be grayed out
and disabled.
To Set the Frequency Deviation
Frequency deviation indicates the variation in the modulating waveform frequency
from the carrier frequency. Tap the Freq.Dev parameter input field to set the FM
frequency deviation.