User`s guide

Expanding Your Measurement Experience 4
Agilent E5505A User’s Guide 91
Refer to Chapter 14, “Evaluating Your Measurement Results” if you are not
familiar with the relationship between the PLL capture range and the peak
tuning range of the VCO.)
The beatnote frequency is set by the relative frequency difference between the
two sources. If you have two very accurate sources set at the same frequency,
the resulting beatnote is very close to 0 Hz.
Searching for the beatnote requires that you adjust the center frequency of one
of the sources above and below the frequency of the other source until the
beatnote appears on the oscilloscope’s display. See Figure 56.
If incrementing the frequency of one of the sources does not produce a
beatnote, you need to verify the presence of an output signal from each source
before proceeding.
NOTE
If the center frequencies of the sources are not close enough to create a beatnote within
the capture range, the system is not able to complete its measurement.
Figure 56 Oscilloscope display of beatnote from test set monitor port
0
V
-1V/div
E5505a oscillo disp beatnote