[Lowfer] One last item before I leave

[Bill Ashlock]

Loopers (and fellow travelers):

 

Earlier in the week I just happened to find an old xerox copy in my files of the derivation for the equation of the amplitude of the signal received from a small loop at a distant receiving site. Also was there was the equation for a small vertical. If equated together one can see the theoretical comparison of the effectiveness of these antennas. At 185K, if the loop is square, and the vertical has the same height as the loop the signals are equal if the total system resistance (Rac) for the vertical is something like 30 ohms and the loop is about 0.2 ohms. This seems to be close to what we have observed over the last 8 years. 

 

Another interesting conclusion from the math is that the advantage of the loop vs the vertical of equal size at 500K should be about 2.8 times improved from the 185K numbers. This doesn't take into acount, however, the effect of the ground or the ease in achieving a lower Rac for the vertical as the frequency of use increases.

 

Bill