ULTRA-SHORT-WAVE TRANSMISSION 



503 



approximately 1 and 4 per cent respectively. There is good coinci- 

 dence. Figure 11 shows active fading on short rollers for 4.7 and 4.65 

 meters, a wave-length difference of approximately 1.1 per cent. There 

 is agreement in major features. Figure 12 shows a case of scintillation 



2:00 RM. 



2:30 P.M. 



3:00 P.M. 



_l 



< 40 

 O 



30 



20 



10 



5:30 A.M. 

 EASTERN STANDARD TIME 



6:00 A.M. 



Fig. 10 — Comparison of simultaneous slow fading on two slightly different wave- 

 lengths, vertically polarized transmission. 



superposed on mild rollers, again for 4.7 and 4.65 meters. The time 

 scale is here magnified three times. An in and out similarity can be 

 seen, especially for the rollers. In the section on theory these simi- 

 larities are further discussed. 



