Phase Shift through a 75m Texas Bugcatcher Coil
			 
			 
			
		
		
		
			
			Richard Harrison wrote: 
 Cecil, W5DXP wrote: 
 "No, just that phasing of RF signals is what is confusing the DC gurus, 
 just like AC phasing confused Edison." 
  
 In W8JI`s pages I found this on the subject of "Mobile antennas, short 
 verticals, loading" : 
 It`s long and Tom warns about taking anything from context, so it should 
 be searched out and read in its entirety. I have no quarrel with most of 
 Tom`s pages but find this statement curious: 
 "When current flows in the transmitter-end of the coil, a magnetic field 
 is created. The time-varying magnetic field causes charges in the other 
 turns to instantly move." 
  
 Instant movement of charges is instant current, and everyone knows that 
 current in a coil lags the voltage. 
  
 Best regards, Richard Harrison, KB5WZI 
  
 
Richard, 
 
This is one of those situations where the exact definitions are  
critical. In the case of "current lags voltage" the current is measured  
through the coil and the voltage is measured between the ends of the coil. 
 
The voltage at the input of the coil (to some reference point) is not  
important; only the voltage across the coil matters. Since there is  
nothing in the problem statement about the coil output voltage it is not  
possible to determine if there is any violation of "current lags  
voltage" or not. 
 
I am not saying anything about the assertion from W8JI. The "current  
lags voltage" principle simply does not settle anything in this case. 
 
73, 
Gene 
W4SZ 
		 
		
		
		
		
		
		
		
		
	
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