HP ESA-L1500A, Руководство пользователя и калибровки

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Chapter 2 41
Getting Started
Making a Measurement
If desired, use the reference level function to place the signal peak at
the top of the screen using the knob, step keys, or numeric keypad.
(Marker functions measure the frequency and amplitude of a signal.)
Figure 2-4 demonstrates the relationship between center frequency
and reference level. The box in the figure represents the spectrum
analyzer display. Changing the center frequency changes the
horizontal placement of the signal on the display. Changing the
reference level changes the vertical placement of the signal on the
display. Increasing the span increases the frequency range that
appears horizontally on the display.
NOTE
Spectrum analyzers with Option 1DP default to display amplitude
values in dBmV when in a log scale mode.
Figure 2-4 Relationship between Frequency and Amplitude
7. Set the marker.
You can place a diamond-shaped marker on the signal peak to find
the signal’s frequency and amplitude.
To activate a marker, press the
Marker
key (located in the
MARKER
section of the front panel). The
Marker Normal
label appears in
inverse video to show that the marker is the active function. Turn
the knob to place the marker at the signal peak.
You can also use the
Peak Search
key, which automatically places a
marker at the highest point on the trace.
Readouts of marker amplitude and frequency appear in the active
function block and in the upper right corner of the display. Look at
the marker readout to determine the amplitude of the signal.