Elevated radials.
I know all the science is good (I am an engineer after all) but what I found
easiest to do when I constructed my 160m inverted-L was to attach a 500' spool
of wire to the base and reel out the wire along previously installed insulated
posts, until my analyzer indicated resonance at the desired frequency. I then
cut off the wire from the spool and terminated it. I plotted the swr curve to
verify things.
I repeated the process for as many elevated radials as I had room for. The
result of adding radials was to widen the useable bandwidth of the antenna.
I think this 'practical' method is advantageous because it instantly accounts
for all the difficult to determine factors and variable that effect a
calculated system design (ground resistance/loss, height of radials above
ground, twists and bends in radial runs, type of wire, inductive affects of
nearby objects, etc)
Rather than trying to measure, estimate or calculate things, I just start
running thru the woods with my spool of wire. Much easier and faster,
especially in the middle of the winter contest season! smile
Marv - wa2bfw
Sent from my iPad
And YES it's cool!
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