Model
8901B
Performance Tests
5.
On the Modulation Analyzer, key in
2.3
SPCL
to
set the modulation range
to
400
kHz.
Allow
at
least two readings
to
pass
.
The display should read between
99
and
101%.
FM Calibration Factor;
400
kHz Modulation Range:
99
101%
6.
On the AMFM test source, set the
test
mode
to
FM. Connect
its
FM+4 output
to
the Modulation
7.
Set the audio analyzer’s oscillator
to
10
kHz
at
1V.
Connect
its
output
to
the audio input of the
Analyzer’s INPUT.
(See
Figure
4-2.)
AMFM
test
source. (See Figure
4-2.)
NOTE
For
this test, if the audio analyzer
has
hating input and output connectors,
the
low
connector should be grounded. Connections should be made to the
high input
or
high output connector.
8.
9.
10.
11.
On the Modulation Analyzer, press FREQ and TRACK MODE. Tune the AMFM
test
source’s
carrier frequency
to
approximately
100
MHz. Press TRACK MODE again
to
turn
it
off.
On the Modulation Analyzer, press FM. Set
LP
FILTER
to
15
kHz and DETECTOR
to
AVG.
Key in
2.0
SPCL
to
set the modulation range
to
automatic.
Adjust the audio analyzer’s oscillator level for
a
Modulation Analyzer display of
20
kHz average
deviation. On the Modulation Analyzer, set RATIO on (with LOG/LIN set for a linear display).
Connect the
FM+32
output of the AMFM
test
source
to
the Modulation Analyzer’s INPUT
without disturbing the AM/FM
test
source’s controls. (See Figure
4-2.)
Multiply the displayed
ratio on the Modulation Analyzer by the calibration factor of
step
4.
(For example,
if
the display
reads
12.52%
REL and the calibration factor of
step
4
is
100.4%,
the result
is
12.52
x
100.4
=
12.57%
REL.) The result should be between
12.35
and
12.65%
REL.
FM Accuracy;
4
kHz Modulation Range:
12.35
12.65%
REL
FM
Distortion,
Accuracy, and
Rejection-1.5
MHz
IF
12.
13.
14.
15.
Connect the FM+4 output
of
the AMFM
test
source
to
the Modulation Analyzer’s INPUT.
(See
Figure
4-2.)
On the Modulation Analyzer, set all LP FILTERS to
off,
DETECTOR
to
PEAK+, and RATIO
off.
Set the audio analyzer’s oscillator frequency
to
100
kHz. Set the level for
a
Modulation Analyzer
display
of
100
kHz peak deviation.
Connect the audio analyzer’s input
to
the Modulation Analyzer’s MODULATION OUTPUT/
AUDIO INPUT. (See Figure
4-2.)
Set the audio analyzer
to
measure the distortion on the
100
kHz signal
at
the MODULATION OUTPUT/AUDIO INPUT (all audio analyzer filters should
be
off).
The distortion should be
0.1%
or less
(-60
dB
or less).
FM Distortion at
100
kHz
Rate;
100
kHz Peak Deviation:
0.1%
Performance Test
2
4-11
To Next Page
Loading...
