PeakTech 4105 Bedienungsanleitung Seite 103

5.5.3 Modulating Waveform Frequency
Press 〖PM Freq〗softkey then set the desired value using knob or keypad. Generally speaking, the
modulating frequency is always lower than carrier frequency.
5.5.4 Modulating Waveform Shape
Press 〖Shape〗 softkey then select 'Shape' to enter the desired wave. Press 【Waveform】 key, then
select most waveforms from above table as modulating waveform, but some waveforms are not
available. Finally, return to PM menu.
5.5.5 Modulating Source
The waveform generator will accept an internal or external modulation source for PM. 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.
5.6 Pulse Width Modulation (PWM)
In Pulse Width Modulation (PWM), the width of a pulse waveform is varied by the instantaneous
voltage of the modulating waveform. You must select PWM before setting up any of the other
modulation parameters. Press 【Modulate】 key then select the PWM using the 〖Mod Type〗 softkey.
The PWM waveform is output using the present settings for the carrier frequency, modulating
frequency, output amplitude, and offset voltage.
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