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Internal Source
• When the internal source is selected, internal modulation signal is the square wave
(built-in and cannot be changed) with 50% duty cycle.
• You can modify the PSK rate to dene the frequency at which the output shifts
between the carrier phase and the modulating phase.
External Source
• When you select external modulation source, the ‘Rate’ option won’t show on the
parameter list and the carriers modulated by an external wave.
• PSK output phase is controlled by logic level presented on the external digital
modulation connector (FSK Trig) on the rear panel.
• For instance, when logic low level presents, carrier phase is output; when logic
high level presents, the modulation phase is output.
Setting PSK Rate
• PSK Rate is available to set up when you select Internal Modulation Source. With
PSK enabled, PSK Rate is 100Hz by default and ranges from 100kHz to 2MHz.
• To change the parameter, switch on PSK interface rst, then use the multipurpose
knob and direction buttons or press Params→Rate softkeys to nish the setting.
Setting Modulating Phase
• Modulating Phase represents the phase variation of the PSK modulated waveform
from carrier waveform. It ranges from 0° to 360°, and defaults to 180°.
• To modify the parameter, switch on PSK interface, then use the multipurpose knob
and direction buttons or press Params→Rate softkeys to finish the setting.
Applications
• Firstly, switch on FSK mode on the Generator.
• Set up a sine wave at 2kHz with amplitude 2Vpp as the carrier signal from the
Generator itself, and PSK rate 1kHz at which the output shifts between carrier
phase and modulation phase, follow the steps as shown below:
Enabling PSK
• Press Menu→Mod→Type→PSK to switch on
PSK function.
Setting Carrier Parameters
• Press Carrier→Type→Sine to select the sine
wave as the carrier signal. Since the default is
sine, there is no need to modify the signal.
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