Phase Shift through a 75m Texas Bugcatcher Coil
			 
			 
			
		
		
		
			
			Cecil Moore wrote: 
 
 Jim Kelley wrote: 
  
 As a suggestion, you might consider increasing the current for the  
 EZNEC simulation on your webpage. 
  
  
 Done as you suggested by changing the current amplitude scale. 
 What do you think about the simulation? Stand by for more 
 additions to that web page. 
 
 From what I gathered, the objective of loading the coil with its  
characteristic impedance was that there would be no reflection.  I was  
therefore surprised when you reported something other than a straight  
line for the current amplitude along the radiator (let alone an  
increase at some point).  It is now apparent that what you are  
actually plotting is the superposed forward and reflected currents,  
and that you have somewhat more than a negligible amount of reflected  
current. 
 
The primary utility in looking at the standing wave profile lies in  
the fact that it gives an idea of what the superposed field intensity  
plot might look like in the near field of the antenna.  But it is  
obviously the currents associated with waves traveling on the antenna,  
both forward and reflected, that actually do the radiating. 
 
I agree with you that it is useful to understand the exact effect the  
loading coil has on the traveling wave, and hence the standing wave  
profile of the antenna.  But I still think it would be prudent to  
explore and understand the precise nature of the delay through the  
coil more thoroughly before making too many assumptions about this. 
 
73, Jim AC6XG 
 
		 
		
		
		
		
		
		
		
		
	
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