Advertisement
Performance
Testa
Model 8902A
Audio
Synthesizer
hequency(Hz)
50 000
100 OOO
50
20
AM Accuracy
16.
On
the Measuring Receiver, press RATIO to turn it
off.
Press PEAK+. Key in 5 . 1 SPCL to set
17.
Set the audio synthesizer frequency
to 10 kHz. Set the audio synthesizer level for a display as
the audio detector time constant
to
slow.
close
as
possible to 80.0% on the Measuring Receiver. Record the display reading below.
AM Limits
(%
REL)
Lower
Actual
Upper
98.9
-
101.1
96.9
-
103.1
98.9
-
101.1
96.9
-
103.1
40.0% reading:
% A M
Audio
Synthesizer
m u e n c y ( ~ z )
20
50
10 000
18. On the Measuring Receiver, key in the reading recorded in step 17 divided by the AM calibration
factor recorded in step 3 then press RATIO. For example,
if
the AM Calibration Factor f r o m
step 3 is 100.
4%
and the reading f r o m step 17 is 80.15%, you would key in 79.83 (that is
,
80.15/1.004), then press the RATIO key.
AM Limits (% REL)
Lower
Actual
Upper
96.9
-
103.1
97.9
-
102.1
97.9
-
102.1
NOTE
ztl
digit at a nominal reading
of
80.0 i s about icO.195
of
the reading in the
RATIO mode.
AM Rejection
2 0 . On the Measuring Receiver, press RATIO to turn it off. Set the HP FILTER to
50
Hz and the
21. Set the audio synthesizer frequency to 1 kHz. Set its level for a Measuring Receiver display of
22. On the Measuring Receiver, press FM. Momentarily disconnect the audio input to the AM/FM
LP
FILTER
to 3 kHz.
50%
AM.
test source and note the residual FM displayed on the Measuring Receiver.
Residual F M
455
kHz I F
Hz
23. Reconnect the audio input of the AM/FM
test
source.
N o t e
the Measuring Receiver's displayed
FM. The displayed FM minus one-half the residual FM noted in
step 22
should be 20 Hz peak
or less.
4-6
AM Rejection (with FM);
455
kHz I F
20 Hz
rev.15DEC88
Advertisement
Chapters
