TOTAL NUMBER OF TRANSMISSIONS PER PERIOD 



500 



O 



in 



<: 



o 



m 



O 



400 - 



300 



1 



PTT 823 N-665 



PTT 839 N = 528 



ALL PITS 



COMBINED N=144 



!00 



00 





 50 



40 



30 - 



20 - 



10 







2 3 



PERIOD 



Figure 14. A comparison of the total number of transmissions received during 6-hour 

 summary periods for PTTs #823, #825, #827. #831, #833, #839 and #840. 



32 



