User Manual 36
5.2.5 Modulating Waveform Frequency
When internal modulation source is selected, press
Frequency
to set the modulating waveform
frequency.
Input the desired frequency value using the numeric keyboard or direction keys and knob.
The modulating waveform frequency ranges from 2mHz to 50kHz, and the default value is
100Hz.
Note: This menu will be grayed out and disabled when other modulation sources except the
internal modulation source are selected.
5.2.6 Modulation Depth
The modulation depth is a percentage that represents the amplitude variation.
Press
Depth
to set DSB-AM modulation depth.
Modulation depth: 0% to 120%. The default is 100%.
At 0% depth, the amplitude is one-
half of the carrier‟s amplitude setting.
At 100% depth, the output amplitude is equal to the specified value.
In >100% modulation, the output amplitude of the instrument would not exceed 10Vpp (50Ω
load).
When "Ext" modulation source is selected, the output amplitude of the instrument is also
controlled by the ±2.5V signal level at the
[Sync/Mod/Trig]
connector at the front panel. For
example, set the modulation depth to 100%, the output amplitude is the maximum when the
modulating signal is +2.5V and the minimum when the modulating signal is -2.5V.
5.3 FM Modulation
A modulated waveform consists of a carrier waveform and a modulating waveform. In FM, the
carrier frequency is varied by the voltage level of the modulating waveform.
5.3.1 Select FM Modulation
Press
Mod->Type->FM
to enable FM function.
When
Mod
is enabled,
Sweep
or
Burst
will be disabled automatically.
After FM is enabled, the instrument will generate FM waveform with the currently specified
carrier and modulating waveforms. To avoid multiple waveform changes, enable modulation
after configuring the other modulation parameters.
