Axcera 430B, Manual

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Axcera-430B Type Acceptance Report Test Report
February 2004 4-6
4.2.6 Audio Modulation
The FM deviation and distortion was measured using the test setup shown in Figure 4-5.
Figure 4-5. Test Setup for Measuring FM Deviation and Distortion
The results of measuring the FM deviation and distortion are shown in Table 4-4.
Table 4-4. Results of FM Deviation and Distortion Measurements
AUDIO
FREQUENCY
DEVIATION
6.25-KHz
DISTORTION
DEVIATION
12.5-KHz
DISTORTION
DEVIATION
25-KHz
DISTORTION
DEVIATION
40-KHz
DISTORTION
100 Hz 0.25% 0.12% 0.09% 0.06%
1000 Hz 0.28% 0.15% 0.09% 0.07%
5000 Hz 0.31% 0.16% 0.12% 0.09%
15000 Hz 0.39% 0.23% 0.24% 0.12%
While maintaining ±25-KHz deviation, the audio input frequency and level were varied
and the response was recorded. The results are shown in Table 4-5.
Table 4-5. Results of Varying the Audio Input Frequency and Level
AUDIO FREQUENCY
RESPONSE
(RELATIVE TO 100 Hz)
50 Hz -0.1 dB
100 Hz 0
400 Hz +0.2 dB
1000 Hz +1.1 dB
2000 Hz +2.9 dB
5000 Hz +8.0 dB
10000 Hz +13.5 dB
15000 Hz +16.6 dB
Tektronix
TSG95
Video
Generator
Transmitter
Under Test
Coupler
50 Ohm
Load
Video
Input
Amber 3501 Dist.
Analyzer/Audio
Signal Generator
Audio Output
Amber 3501
Audio
Generator
Audio
Input
RF
HP 8901A
Modulation
Analyzer