HP 8901B Operation And Calibration Manual page 346

Performance Tests Model 8901B
Audio
Synthesizer
Frequency (HZ)
50
000
100 000
50
20
A M Accuracy
16. On the Modulation Analyzer, press RATIO
to
turn it off. Press PEAK+. Key in 5.1 SPCL
to
set
the audio detector time constant to slow.
17. Set the audio synthesizer frequency to 10 kHz. Set its level for a display of 80% AM times the
calibration factor of step 3. (For example,
if
the calibration factor of step 3 is 100.495, set the
level for a display of 80.3% AM.)
18. On the Modulation Analyzer, key in 80 and press RATIO. Set the audio synthesizer to the
frequencies shown in the following table (without changing the level). For each setting, the
Modulation Analyzer's display should read between the limits indicated in the table.
~ ~~ ~
AM
Limits
(YO
REL)
Lower Actual Upper
98.9
-
101.1
96.9
-
103.1
98.9
-
101.1
96.9
-
103.1
r
Audio
Synthesizer
heauency(Hzl
I
I I
I
I
AM Limits
(%
REL)
~ o w e r
I
~ c t u a l
I
upper
NOTE
fl digit at a nominal reading
of
80.0
is
about fl%
of
the reading in the
RATIO
mode.
20
50
10 000
96.9
-
103.1
97.9
-
102.1
97.9
-
102.1
AM
Rejection
20. On the Modulation Analyzer, press RATIO to turn it off. Set the H P FILTER to 50
H z
and the
21. Set the audio synthesizer frequency to 1 kHz. Set its level for a Modulation Analyzer display of
22. On the Modulation Analyzer, press FM. Momentarily disconnect the audio input to the A M F M
LP FILTER to 3 kHz.
50% AM.
test source and note the residual FM displayed on the Modulation Analyzer.
Residual FM; 455 kHz IF:
Hz
23. Reconnect the audio input of the AMFM test source. Note the Modulation Analyzer's displayed
FM. The displayed FM minus one-half the residual FM noted in step 22 should be 20
H z
peak
or less.
AM Rejection (with FM); 455
kHz
IF: 20
H z
4-6 Performance Test 1