Hantek HDG2000B Series, Руководство пользователя

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User Manual 34

Press Depth to set 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.
5.2 DSB-AM Modulation
In the Double-sideband AM signal, there are only two side frequencies, and there is no carrier
component. Its frequency bandwidth is still twice the frequency of the modulated signal.
5.2.1 Select DSB-AM Modulation
Press Mod->Type->DSB-AM to enable DSB-AM function.

When Mod is enabled, Sweep or Burst will be disabled automatically.

After DSB-AM is enabled, the instrument will generate DSB-AM waveform with the currently
specified carrier and modulating waveforms. To avoid multiple waveform changes, enable
modulation after configuring the other modulation parameters.
5.2.2 Carrier Waveform Shape
DSB-AM carrier shape: Sine (default), Square, Ramp, Pulse, Arbitrary (except DC) or Harmonic
waveform.

Press the front panel key Sine , Square , Ramp , Pulse , Arb -> Type or Harmonic to select a
desired carrier waveform shape.

Noise and DC could not be used as carrier waveform.
5.2.3 Carrier Frequency
The maximum carrier frequency varies by function, as shown below. The default is 1 KHz for all
functions.
Carrier Waveform Frequency Range
Sine
1μHz to 100MHz
Square
1μHz to 30MHz
Ramp
1μHz to 4MHz