PeakTech 4105 Bedienungsanleitung Seite 102

5.4.5 Modulating Source
The waveform generator will accept an internal or external modulation source for AM. 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.
5.5 Phase Modulation (PM)
A modulated waveform consists of a carrier waveform and a modulating waveform. PM is very similar
to FM, but in PM the phase of the modulated waveform is varied by the instantaneous voltage of the
modulating waveform.
5.5.1 Set Carrier
Firstly, set the shape, frequency, amplitude and offset of Carrier Waveform. You can select most
waveforms from above to be carrier, but some waveforms are not available.
5.5.2 Phase Deviation
Press 〖Phase Dev〗softkey then enter the desired value using knob or keypad. The phase deviation
setting represents the peak variation in phase of the modulated waveform from the carrier waveform.
If at positive peak value, the phase of output signal increases one phase deviation. If at negative
peak value, the phase of the output signal will decrease one phase deviation.
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