Ralph Mowery wrote: 
"The 1/4 wave vertical at about 16 or 20 inches will tend to put much of 
the signal towards the sky like a round ball would look laying in the 
water." 
 
The mental image Ralph`s statement creates in my mind is mistaken. The 
1/4-wave vertical antenna over a reflecting plane has a pronounced null 
at its tip. The pattern is no hemisphere. 
 
See Fig 3 on page 3-5 of the 19th edition of the ARRL Antenna Book for 
the vertical radiation pattern of a 1/4-wave vertical antenna over 
earth. Over a ground plane antenna at any elevation, the pattern is 
similar, that is, there is a pronounced null at its tip. 
 
Best regards, Richard Harrison, KB5WZI 
 
		 
		
		
		
		
		
		
		
		
	
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