Agilent Technologies E7405A User Manual
Chapter 1
19
Making Basic Measurements
Resolving Small Signals Hidden by Large Signals
Resolving Signals Example:
Resolve two input signals with a frequency separation of 155 kHz and
an amplitude separation of 60 dB.
an amplitude separation of 60 dB.
1.
Connect two sources to the analyzer input as shown in
.
Figure 1-9
Setup for Obtaining Two Signals
2.
Set one source to 300 MHz at
−
10 dBm.
3.
Set the second source to 300.155 MHz, so that the signal is 155 kHz
higher than the first signal. Set the amplitude of the signal to
higher than the first signal. Set the amplitude of the signal to
−
70 dBm (60 dB below the first signal).
4.
Set the analyzer as follows:
a.
Press
Preset
,
Factory Preset
(if present).
b.
Set the Y-Axis Units to dBm by pressing
AMPLITUDE
,
More,
Y-Axis Units,
dBm
.
c.
Set the center frequency to 300 MHz by pressing
FREQUENCY,
Center Freq
, 300,
MHz
.
d.
Set the span to 2 MHz by pressing
SPAN,
Span
, 2,
MHz
.
NOTE
If the signal peak is not present on the display, do the following:
1.
Increase the span to 20 MHz by pressing
SPAN,
Span
, 20,
MHz
.
The signal should now be visible.
2.
Press
Peak Search
,
FREQUENCY
,
Signal Track
(On)
3.
Press
SPAN
, 2,
MHz
to bring the signal to center screen.
4.
Press
FREQUENCY
,
Signal Track
(Off)
e.
Set the resolution bandwidth to spectrum analyzer coupling by
pressing
pressing
BW/Avg
,
Resolution BW
(SA).