
4. Impulse and Resolution Bandwidth Selectivity Test
4.
Impulse
and
Resolution
Bandwidth
Selectivity
!kst
Related
Adjustment
Specification
Description
Note
Equipment
Procedure
3 MHz Bandwidth Filter Adjustments
2 1.4 Bandwidth Filter Adjustments
Step Gain and 18.4 MHz Local Oscillator Adjustments
60
dB/6
dB
bandwidth ratio:
<ll:l,
3
MHz
to
100
kHz
<8:
1, 30
kHz
to
30 Hz
60
dB
points on 10 Hz bandwidth are separated by
~100
Hz
Bandwidth selectivity is found by measuring the 60
dB
bandwidth
and dividing this value by the 6
dB
bandwidth for each resolution
bandwidth setting from 30 Hz to 3 MHz. The 60
dB
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
C2-22)
and connect the CAL
OUTPUT to RF INPUT.
2. Key in spectrum analyzer control settings as following:
[CENTER FREQUENCY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
MHZ
FREQUENCY SPAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.20
MHz
!m,
j.
.,.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.,“,g
VIDEO BW
SWEEP
. . .
::
::::::
::
:::
::::
:::
:::::::
:::
::::::
.‘.‘.‘.~.~.~.~.~.~.~.~
.‘.‘cm]
3. On the spectrum analyzer, press MARKER
CNORMAL-]
and position
the marker at the peak of the signal trace using the DATA knob.
Press MARKER In] and position the movable marker 60
dB
down
from the stationary marker on the positive going edge of the signal
trace (the MARKER
Ia]
amplitude readout should be -60.00
dB
fl.OO
dB).
It may be necessary to press SWEEP
ICONT)
and to
adjust (CENTER FREQUENCY) so that both 60
dB
points are displayed
(see Figure 4-5).
Option 462 4-13
Commentaires sur ces manuels