Example: 
INSPECTING AND TESTING THE RADIOSONDE 1S} ie) 
Pressure Contact 6.0 = 992 millibars 
Pressure Contact 7.0 = 980 millibars 
Find Pressure at Contact 6.2 
(1) 
(2) 
(3) 
992 - pressure at 6.0 (lower contact) 
980 - pressure at 7.0 (higher contact) 
12 - difference 
x .2 - tenths value of pressure contact 
2.4 - product 
992.0 - pressure at lower contact 
-2.4 - product obtained in 2. 
989.6 - result = 990 mb pressure at 6.2 contacts when pres- 
sure is rounded off to nearest whole millibar. 
To determine the pressure contact value from the pressure value, 
use the following procedure: 
a. 
b. 
Example: 
If pressure value falls on a whole contact (5.0, 10.0, 12.0), 
use contact value corresponding to that pressure. 
If pressure value falls between two whole pressure contacts: 
(1) Determine the pressure difference between the two whole 
pressure contacts that bracket the desired pressure. 
(2) Subtract pressure value for which contact value is de- 
sired from pressure value at next lower whole contact 
(higher pressure). 
(3) Divide value obtained in (2) by value obtained in (1). 
Result is tenths value desired. Add this value to lower 
pressure contact. 
Pressure value for which contact value is desired = 988 mbs 
(rounded off to nearest whole millibar). 
(1) 
1-1-69 
992 - pressure at 6.0 (lower contact) 
980 - pressure at 7.0 (higher contact) 
12 - difference 
FMH#3 
