28 UTG2000B Series
arbitrary wave and noise. If need to change the waveform, press Param
→
ModWave .
●
Square wave: duty ratio is 50%
●
Rising Ramp Wave: symmetry degree is 100%
●
Falling Ramp Wave: symmetry degree is 0%
●
Arbitrary Wave: when arbitrary wave is modulated waveform, DDS function generator limits
arbitrary wave length as 4kpts
2) External Source
When modulation source is external, parameter list will hide the modulation wave option and
modulation frequency option, and carrier waveform will be modulated by an external waveform.
AM modulation depth is controlled by ±5V signal level of external modulation input terminal
Modulation In connector). For example, if modulation depth value is set to 100%, AM output
amplitude is the maximum when external modulation signal is +5V, AM output amplitude is the
minimum when external modulation signal is -5V.
Set Modulation Wave Frequency
When modulation source is internal, frequency can be reset. Default of modulation wave frequency
is 100Hz. Press Param
→
Mod Freq to change. Modulation frequency range: 2 MHz~1MHz. When
modulation source is external, parameter list will hide the modulation wave option and modulation
frequency option, and carrier waveform will be modulated by an external waveform. The range of
external signal frequency is 0Hz~ 20 kHz.
Set Modulation Depth
Modulation depth indicates the extent of amplitude variation which is expressed as percentage.
Settable range of AM modulation depth is 0% ~ 120%, and the default is 100%. When modulation
depth is set to 0%, the constant amplitude (half of the carrier wave amplitude)is output. Output
amplitude changes as modulation waveform changes when modulation depth is set to 100%. The
instrument output a peak-peak voltage less than ±5V
(50Ω
terminal) when modulation depth is
more than 100%.
If need to change, press Param
→
Depth in amplitude function interface. When modulation
source is external, output amplitude of the instrument is controlled by
±
5V signal level of external
modulation input terminal (Modulation In connector) in rear panel. For example, if modulation
depth value in parameter list has been set to 100%, AM output amplitude is the maximum when
external modulation signal is +5V, AM output amplitude is the minimum when external modulation
signal is -5V.
Comprehensive Example
Set a sine wave with 200Hz from the internal of the instrument as a modulation signal and a square
wave: frequency =10 kHz, amplitude of 200mVpp and duty ratio of 45% as a carrier wave signal.
Finally, set modulation depth to 80%. Specific steps are seen as following: Noise: White Gauss noise
3) Enable Amplitude Modulation (AM) Function
Press Menu
→
Mod
→
Type
→
AM in turn.
Summary of Contents for UTG2122B
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