User Manual

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5.6.3 Modulating Waveform Frequency
Press 〖PWM Freq〗softkey then set the desired value using knob or keypad. Generally speaking, the
modulating frequency is always lower than carrier frequency.
5.6.4 Modulating Waveform Shape
Press 〖Shape〗softkey then select ‘Shape’ to enter the desired wave. Press 【Waveform】 key, then
select one of most waveforms from above table as modulating waveform, but some waveforms are
not available. Finally, return to PWM menu.
5.6.5 Modulating Source
The waveform generator will accept an internal or external modulation source for PWM. Press
〖Source Int/Ext〗softkey. It’s available to set modulating frequency and modulating waveform if
‘Internal’ source is selected. But if you select External source, the carrier waveform is modulated with
an external waveform. The frequency deviation is controlled by
the ±5 V signal level present on the rear-panel Modulation In connector.
5.7 Sum Modulation
In Sum Modulation (Sum), the modulating signal is added to the carrier waveform. Press 【Modulate】
key then select the SUM using the 〖Mod Type〗softkey. The Sum waveform is output using the
present settings.
5.7.1 Set Carrier
Firstly, set the shape, frequency, amplitude and offset of Carrier Waveform. In Sum, the
instantaneous voltage of output waveforms equals to sum voltage of carrier waveform and
modulating waveform. You can select one of most waveforms from above table to be carrier, but
some waveforms are not available.