300 100 30 10 



10,000 



5000 



FREQUENCY (megacycles) 



3 1 03 0.1 0.03 0.01 



2000 

 1000 



NAVIGATIONAL 500 



RANGE 

 (statute miles) 



200 



100 



50 



20 

 10 









. 











^ 







s 





NIGHT 



LOR AN 



-f 









DAY 



A 



LORAN-A 



'/ 











A 





/ 



/ 













\ 





/ 

 / 

















^ . 



/ 

 f 

















LORAN- 



A 









SK^ 



t' WAV 



:s 

































3 10 30 100 300 1000 3000 10,000 30,000 



WAVE LENGTH (meters) 



FIGURE III- 7 AVERAGE SKY-WAVE TRANSMISSION 



RANGES 



300 100 30 10 



10,000 



5000 



2000 

 1000 



NAVIGATIONAL '°° 



RANGE 

 (statute miles) 200 



100 



50 



20 

 10 



FREQUENCY (megacycles) 



3 1 03 0.1 0.03 0.01 



















































PULSE 1 



FRANSMi; 



>SION 











.LORAN 





^ 





y 



^ — " 



^^ 













> 











COK 



TINUOU* 



WAVE 



D 



iCCA 











T 



RANSMISStON r 



ADIO 

 ANGE 















BROADCASTING 



y\ 1 

























10 30 100 300 1000 3000 10,000 30,000 



WAVE LENGTH (meters) 



FIGURE III-8 MAXIMUM RANGE AT WHICH GROUND- 



WAVE TRANSMISSION IS ESSENTIALLY 

 FREE FROM SKY-WAVE INTERFERENCE 



24 



