PeakTech 4035 Bedienungsanleitung Seite 93

7.9.5 Modulating waveform:
It is able to set modulating waveform shape if internal modulating signal is used. Press 〖SineModu〗
softkey to select "sine modulation", "square modulation", "triangle modulation" or "ramp modulation".
Modulating waveform shape setting would be ignored if external modulating signal is used.
7.9.6 Modulating source:
The function generator will accept an internal or external modulation source for AM. Press 〖Int
Modu〗softkey to select "external source". The modulating signal is inputted from the rear panel "Modulation
In" connector for AM. If the amplitude of the external modulating signal is ±5V, the phase shift setting and
the display value accord with the real phase shift. Otherwise, the phase shift setting and display value are
not accurate.
7.9.7 Sync output:
In PM, the generator outputs a sync signal from the front panel "Sync" connector, which is square wave with
TTL level and 50% duty cycle, its frequency if equal to modulating frequency and its phase is referenced to
the phase of the modulating signal.
7.10 To set the phase modulation (PM) (P 4050)
In PM, the phase of the carrier is varied by the instantaneous voltage of the modulating waveform. Follow
the steps to set a PM waveform with 2 kHz carrier frequency, 1 kHz modulating frequency and 180° phase
offset.
First, to set the sine waveform:
7.10.1 Press【Mod】 key to enter the interface of modulating output and select modulating mode.
7.10.2 Press〖PM〗softkey to enter the interface of PM modulate and "FM by Square" is displayed on the
upper-left of screen.
7.10.3 The current selected option is "carrier frequency"; use numeric keys or knob to set carrier frequency
to 2 kHz.
7.10.4 Press 〖Modu Freq〗softkey to select "modulating frequency" and set it to 1 kHz by using numeric
keys or knob.
7.10.5 Press〖phaseOffs〗softkey to select "phase offset" and set it to 180°by using numeric keys or knob.
7.10.6 Press〖SineModu〗softkey and select square modulation.
After setting, the generator outputs PM modulating waveform with the parameters.
7.11 Pulse width modulation (PWM) (only P 4050)
In PWM, the pulse width of the carrier is varied by the instantaneous voltage of the modulating signal, and
the waveform shape of the carrier must be pulse.
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