TB 9-6625-152-24
Table 23. FM Modulation Analyzer 100 Hz Modulation Rate.
Signal generator
Test instrument
Output
Indication limits (kHz)
Frequency
Mod rate
FM deviation
(MHz)
(MHz)
(Hz)
(kHz)
Min
Max
5.5
100
20
5.5
18.8
21.2
100
100
20
100
18.8
21.2
500
100
20
500
18.8
21.2
1000
100
20
1000
18.8
21.2
100
100
50
100
45.5
54.5
100
100
60
100
54.6
65.6
100
100
1
100
0.91
1.09
(13) Set measuring receiver high pass filter to 300 Hz and low pass filter to 15 kHz.
(14) Set TI as listed in (a) through (c) below:
(a) Press Tx TEST, [Mod Meter], [IF Filter] and [300 kHz].
(b) Press AF TEST, [AF Filter] and [15 kHz LP].
(c) Press Tx TEST, [Tx Freq], 5.5, MHz keys.
(15) Set signal generator for a 5.5 MHz, 6 dBm output with FM modulation of 20 kHz
deviation at a 10 kHz modulation rate.
(16) Adjust signal generator FM deviation for first value listed in FM Deviation
column of table 24 as indicated on measuring receiver. If TI displayed FM LEVEL
indication is not within limits specified in first row of table 24 for specific model, perform
b below.
(17) Repeat technique of (14) (c) through (16) above for signal generator outputs and
TI settings listed in table 24. If TI displayed FM LEVEL indications are not within limits
specified in table 24 for specific model, perform b below.
Table 24. FM Modulation Analyzer 10 kHz Modulation Rate.
Signal generator
Test instrument
Output
Indication limits (kHz)
Frequency
Mod rate
FM deviation
(MHz)
(MHz)
(kHz)
(kHz)
Min
Max
5.5
10
20
5.5
18.8
21.2
100
10
20
100
18.8
21.2
500
10
20
500
18.8
21.2
1000
10
20
1000
18.8
21.2
100
10
50
100
45.5
54.5
100
10
60
100
54.6
65.6
100
10
1
100
0.91
1.09
(18) Set signal generator output to minimum and disconnect equipment setup.
b. Adjustments. Perform adjustments in Section IV below.
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