PT52N3 CH3 





20 



1 1 1 



1 ' 1 ' 1 ■ 



1 





10 



- 



1 













s 







D 

 m 



-10 



- 



- 





-20 



- 



- 





-30 



- 



- 





-40 



- 



- 





-50 



< 1 1 



I.I.I 



Figure 17. Record depicting minimum negative pressure, 

 Channel 3 



PT154N4CH4 



T— 1 r 



Figure 18. Record depicting minimum negative pressure, 

 Channel 4 



35 



