Jim,
Think of a cage connection rather than a single wire to a shunt fed tower
and its benefit. The cage larger diameter causes an impedance change and
also makes it a more broad-banded fat conductor.
Benefits of a in ground grid have been established. A partial grid connected
to radials already in place would not be a negative. Antennas that are fat
the entire length have a lower Q, lower impedance at the far end, and are
wider in frequency.
I think of my in ground radial system system in a similar fashion.
My ground radial system has a perimeter wire and has worked well. Working in
the DX contest this weekend on 160 meters with 100 watts. Only a few request
for a call repeat.
The best benefit of a perimeter wire : ... It allows each wire to be
individually disconnected at the tower base. The disconnected wire can be
checked with an ohmmeter against the remaining radials to
confirm continuity. I check them every few years, and pull any broken
wires up to splice or replace.
73
Bruce-K1FZ
www.qsl.net/k1fz/beveragenotes.html
I wonder if there is supporting analysis for connecting the radial ends??
I have around 80 elevated radials that range from 50 foot lengths, running
east and west, and 25 foot lengths running north and south (all of that a
function of being geographically challenged). I have not tied the bitter
ends together....never really thought about it when I put the radial field
together but seem to recall reading something about tieing the ends
together and having a well bounded complete "grid" underthe antenna.
Thoughts? I tend to think it wouldn't hurt... 72, Jim Rodenkirch K9JWV
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