TB 9-6625-2188-35
Harmonic
20 Hz
50 kHz
100 kHz
values
2d
9.5
10
10.5
3d
6.0
6.5
7
4th
4.5
5
5.5
5th
3.5
4
4.5
(11) Compute arithmetic difference between the two numerically lower dB values (2d
and 3d) harmonic recorded in (10) above.
NOTE
If difference value falls between two difference values in table
Example:
-112.2
-108.0
4.2 = difference value
(12) Locate difference value (4.2) in table 7 below and determine corresponding
additive factor (1.42). Algebraically add additive factor to the numerically lower dB value
(2d harmonic) of (10) above.
Example:
-108.0
1.42
-106.58 = resulting number
Difference
Additive
Difference
Additive
values
factors
values
factors
0.0
3.01
10.0
0.41
0.5
2.77
11.0
0.33
1.0
2.54
12.0
0.27
2.0
2.12
13.0
0.21
3.0
1.76
14.0
0.17
4.0
1.46
15.0
0.14
5.0
1.19
16.0
0.11
6.0
0.97
17.0
0.09
7.0
0.79
18.0
0.07
8.0
0.64
19.0
0.05
9.0
0.51
20.0
0.04
(13) Repeat technique above using resulting number from (12) above and the next
numerically lower dB value (4th harmonic) of (10) above.
CHANGE 1
8
PIN: 063912-001
