103
Making Time-Gated Measurements
Gated LO Measurement
Figure 8-8  Pulsed and Gated Signal
9 Turn off the pulse 
modulation on ESG #1.
• Press Pulse, Pulse so 
that Off is selected.
Notice that the gated spectrum is much 
cleaner than the ungated spectrum (as seen 
in the Pulsed-RF FM Signal above). The 
spectrum you see with the gate on is the 
same as a frequency modulated signal 
without being pulsed. The displayed 
spectrum does not change and in both 
cases, you can see the two low-level 
modulation sidebands caused by the 
narrow-band FM. 
Step Action Notes