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Model 8902A
Performance Tests
5. On the Measuring Receiver,
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 AM/FM test source, set the test mode to FM. Connect its F M i 4 output to the Measuring
7. Set the audio analyzer's oscillator to 10 kHz at 1V. Connect its output to the audio input of the
Receiver's INPUT. (See Figure 4-2.)
AM/FM test source. (See Figure 4-2.)
NOTE
For [his
test,
[ f t h c audio analyzer has jloating inpirt and
oirtpirt
conncWws,
{he low
connwtor
sltoiild hc~ groirndcd. Conncciions shoirld bc madc
to
the
high
inpill
or
high
oiilpirf
connccfor.
8. On the Measuring Receiver, press FREQ and TRACK MODE. Tune the AM/FM test source's
carrier frequency to approximately
100
MHz. Press TRACK MODE again to turn it o f f .
9. On the Measuring Receiver, press FM. Set LP FILTER to 15 kHz and DETECTOR t o AVG.
Key in 2.0 SPCL to set the modulation range to automatic.
10. Adjust
the
audio analyzer's oscillator level for a Measuring Receiver display of 20 kHz average
deviation. On the Measuring Receiver, set RAT10 on (with LOG/LIN set for a linear display).
11. Connect the FMi-32 output of the AM/FM test source to the Measuring Receiver's INPUT
without disturbing the AM/FM test source's controls. (See Figure 4-2.) Multiply the displayed
ratio on the Measuring Receiver by the calibration factor of step 4. (For example, if the display
reads 12.529'0 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 12.65Yo REL.
FM Accuracy; 4 kHz Modulation Range: 12.35
12.65% REL
FM Distortion, Accuracy, and Rejection--1.5
MHz
IF
12. Connect the F M i 4 output of the AM/FM test source to the Measuring Receiver's INPUT.
(See Figure 4-2.)
13. On the Measuring Receiver, set all LP FILTERS to
off,
DETECTOR to PEAK+, and RATIO
O f f .
14. Set the audio analyzer's oscillator frequency to 100 kHz. Set the level for a Measuring Receiver
display of 100 kHz peak deviation.
15. Connect the audio analyzer's input to the Measuring Receiver's MODU LATlON OUTPUT/
AUDIO INPUT. (See Figure 4-2.) Set the aiidio analyzer to measure the distortion on the 100
kHz signal at the MODULATION OUTPUT/AUDlO INPUT (all audio analyzer filters should
be
off).
The distortion should be O.lo/o or less (-60 dB or less).
FM Distortion at 100 kHz Rate; 100 kHz Peak Deviation:
0. 1%
4-1 1
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