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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UR RST IS ... ... ..9 QSB QSB - hw? BK
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