
4.
Resolution
Bandwidth
Selectivity
YLkst
Related
Adjustments
Specification
Description
Equipment
Note
Procedure
(For instruments with Option 462, refer to Chapter 4.)
3 MHz Bandwidth Filter Adjustments
21.4 MHz Bandwidth Filter Adjustments
Step Gain and 18.4 MHz Local Oscillator Adjustments
60
dB/3
dB
bandwidth ratio:
<15:1, 3 MHz to 100
kHz
bandwidths
<13:1,
30
kHz
to 10
kHz
bandwidths
<
11: 1,
3
kHz
to 30 Hz bandwidths
60
dB
points on 10 Hz bandwidths are separated by
~100
Hz
Bandwidth selectivity is found by measuring the 60
dB
bandwidth
and dividing this value by the 3
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.
None required
Performance Test 3, RESOLUTION BANDWIDTH ACCURACY TEST,
must be performed before starting this test.
1.
Press
@7ZiZj.
2. Connect CAL OUTPUT to RF INPUT.
3. Key in analyzer control settings as follows:
&ENTER FREQUENCY]
. . . . . . . . . . . . . . . . . . . . . . .
FREQUENCY
SPAN)
. . . . . . . . . . . . . . . . . . . . . . . . .
I-,
~
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VIDEO BW
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
SWEEP
@Z%j
100 MHz
.20
MHz
.
3 MHz
. .
100 Hz
4. Press MARKER
(j-j
and position marker at peak of signal
trace. Press MARKER
(ZJ
and position movable marker 60
dB
down from the stationary marker on the positive-going edge
of the signal trace (the MARKER A amplitude readout should
be -60.00
dB
f
1.00
dB).
It may be necessary to press SWEEP
ICONT)
and adjust (CENTER FREQUENCY) so that both 60
dB
points
are displayed. (See Figure 2-6.)
5. Press MARKER In] and position movable marker 60
dB
down from
the signal peak on the negative-going edge of the signal trace (the
MARKER A amplitude readout should be .OO
dB
f0.50
dB).
6. Read the 60
dB
bandwidth for the 3 MHz resolution bandwidth
setting from the MARKER A frequency readout (Figure 2-6) and
record the value in Table 2-6.
2-14 Performance Tests
Commentaires sur ces manuels