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Frequency offset note:
Offset must be less than or equal to carrier frequency;
Sum of the offset and carrier frequency must be less than or equal to the maximum
frequency of the function selected.
For the external source, offset is controlled by the ±5V level on the [Modulation In]
connector. +5 V plus the selected offset, lower external signal levels generate less offset
and negative signal levels reduce the frequency below the carrier frequency.
2.2.3 Phase Modulation (PM)
Modulated waveforms consist of carrier waves and modulation waveforms. In PM (Phase
Modulation), the phase of the carrier wave changes with the instantaneous voltage of the
modulation waveform.
The carrier wave for phase modulation can be set with the function keys
of
on the front panel.
Press
→ Type→ PM and enter the interface as shown in Figure 2-23.
Internal
modulation
Frequency
Set modulation wave frequency (2mHz~20kHz)
Frequency
offset
Set the offset between the frequency of modulation
and the carrier.
Modulation
wave
Select internal modulation signal:
Sine/Square/Triangle/UpRamp/DnRamp
External
modulation
Frequency
offset
When external modulation is selected, the
modulation signal is input by the [Modulation
In] on the rear panel. And only the parameters
of Offset is needed setting here.