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Re: Topband: Effect of current max not at base of vertical

To: topband@contesting.com
Subject: Re: Topband: Effect of current max not at base of vertical
From: W9UCW@aol.com
Date: Sat, 24 Sep 2011 21:17:44 -0400 (EDT)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
This may or may not be significant to the  discussion. In the 1970's I was 
using a 120 foot insulated base vertical as my  main transmit antenna. I had 
12,000 feet of #12 copper radials from 90 to 200  feet in length buried 
about 3 inches in the ground surrounding the antenna. It  was located near 
Minooka, Illinois in a wooded rural area.
 
As an experiment, I asked several friends who  were located from one to 
twelve miles away to record my signal strength at  their location each day for 
one month at a specific power of 100 watts of  carrier. Then I had my tower 
climbing buddy, Jack, W9YF (SK) put a resonator  tuned to 1850 on top of the 
vertical. 
 
I had to modify the base matching system. It had  been a shunt coil to 
ground. It now required a parallel resonant circuit from  the base of the tower 
to ground with the coax from the rig tapped onto the  coil.
 
When my friends reported the signal strength  they now recorded, it was 
from a half to a full "S" unit more than their  original readings. Now that's 
certainly not very scientific, but their comments,  assuming all groundwave  
readings, were sure interesting to  me.
 
73, CU on TopBand, Barry,  W9UCW
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