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Old May 10th 04, 12:24 PM
Ron
 
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Dave,

I didn't come here to fence with you guys. I know nothing about the
relative efficiency of antenna systems.

You could be right and the effiency of a tuned dipole "may" be 2%,
which in my mind means if it were replaced with a regular dipole, the
signal strength at a remote location would increase 50 times, but that
certainly cannot be determined that with that brand of math.

Sorry,

Ron

On Mon, 10 May 2004 00:20:55 GMT, Dave Shrader
wrote:

Ron wrote:

On Sun, 09 May 2004 17:26:05 GMT, Dave Shrader
wrote:

SNIP

So you can use the formula I^2*R (which is for finding P) without
knowing the variable "I" to find the resistance (Ra)?

I don't think so. Unless you have a magic wand, Harry Potter :-)

Ron


You certainly can!!

Total power to the antenna SYSTEM = I^2*(Rr + Ra + Rg).

Total power radiated = I^2*(Rr).

When you divide the two terms to get efficiency the I^2 term cancels.
This leaves Rr/(Rr + Ra + Rg). The current terms drops right out!!

DD