TB 9-4931-413-40
(c) Attenuator switch to 110 db.
Height in feet
1200
0
1000
800
2
4
600
6
400
8
10
300
12
200
0
2
4
6
8
10
Height in Kilometers
above sea level
INCHES of Hg
10
15
20
25
30
1000 1100
200
300
400
500
600
700
800
900
MilliBars
Figure 1. Pressure correction chart.
C59
C56
C60
R56
R52
C71
C53
Microphone
sensitivity
adjustment
Figure 2. Sound-level meter (model 1551-C) - internal view.
5