RADIO PROPAGATION 75 



given in Column 6 these conditions are fulfilled and the proportionality- 

 factor is given in Columns 7, 8 and 9 for three frequencies. When the 

 frequency is large compared with that given in Column 6, (2 » 1 and 

 the parameter x of Fig. 2 is proportional to the distance and the first 

 power of the frequency. This proportionality factor is given in 

 Column 10 for a frequency of 50 mc. 



The parameter q = 2cr/f of Figs. 5-12 is given in Columns 10, 11 

 and 12 for three frequencies. 



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