4. Impulse and Resolution Bandwidth Selectivity
3 MHz Bandwidth Filter Adjustments
2 1.4 Bandwidth Filter Adjustments
Step Gain and 18.4 MHz Local Oscillator Adjustments
60
bandwidth ratio:
3 MHz to 100
1, 30
to 30 Hz
60
points on 10 Hz bandwidth are separated by
Hz
Bandwidth selectivity is found by measuring the 60
bandwidth
and dividing this value by the 6
bandwidth for each resolution
bandwidth setting from 30 Hz to 3 MHz. The 60
points for the 10
Hz bandwidth setting are also measured. The CAL OUTPUT provides
a stable signal for the measurements.
Resolution Bandwidth Accuracy Test must be performed before this
test.
None required
1. On the spectrum analyzer press
and connect the CAL
OUTPUT to RF INPUT.
2. Key in spectrum analyzer control settings as following:
[
CENTER FREQUENCY
) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
100
FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MHz
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIDEO BW
SWEEP . . .
3.
On
the spectrum analyzer, press MARKER
and position
the marker at the peak of the signal trace using the DATA knob.
Press MARKER In] and position the movable marker 60
down
from the stationary marker on
the
positive going edge of the signal
trace (the MARKER
amplitude readout should be -60.00
fl.OO
It may be necessary to press SWEEP
and to
adjust
(
CENTER FREQUENCY
)
so that both 60
points are displayed
(see Figure 4-5).
Option 462 4-13