User`s guide

Chapter 2 Front Panel Operations RIGOL
DSG3000 User’s Guide 2-39
LF Output
LF output refers to the output of the low-frequency signal generated by the internal
generator of the RF signal source. When analog modulation is enabled, LF outputs
the internal modulating signal. If the analog modulation is disabled, LF outputs
several common waveforms. You can set the frequency and amplitude of the
low-frequency signal.
To Enable the LF Output
Press LF to enable the LF output. The backlight of the key goes on and the LF label
is displayed in the status bar and the function status area in the user interface. At this
point, the [LF OUTPUT] connector (as shown in the figure below) outputs the LF
signal according to the current configuration.
To Set the LF Parameters
Press  LF to set the “Waveform”, “Level” and “Freq” of the LF output signal.
Explanation
1. When the AM or FM/ Φ M function and MOD switch are enabled, and the
internal modulation source is selected, Waveform and Freq are grayed out
and disabled. At this point, the waveform and frequency of the LF output
signal should be set via Waveform and Freq (or Rate) under the AM or
FM/
Φ M function and the amplitude of the LF output signal (namely the
modulating signal) should be set via Level.
2. When all analog modulations which use the internal modulation source are
turned on simultaneously and all modulation frequencies and waveforms are
consistent, the parameter settings of LF output signal are determined by the
last configuration.
3. Turn on the MOD switch; any one of the AM or FM/ Φ M function is enabled
and “Ext” modulation source is selected; all menus under the LF are grayed
out and disabled; you cannot set the frequency and amplitude of the LF
output signal. At this point, the actual LF output is consistent with the
external modulating signal. When “Int & Ext” modulation source is selected,
LF output frequency is half the frequency of internal modulating signal.