I have a Butternut HF9V for use as a second radio antenna in contests. It
is located on the roof of my garage, which is a slightly tilted surface
roughly 30 x 40 feet, made up of 4 x 8' galvanized steel sheets.
It seemed to me that I could make a decent ground plane from the roof
panels if I could figure out a way to connect them all together and connect
the antenna's ground terminal to them. However, the roof is covered with
asphalt roof paint, and pigtailing the individual sheets together sounded
like a lot of work. As an alternative, I took a 125-foot piece of wire,
connected it to the ground terminal, and laid it out on the roof so that it
traverses every panel. My thought was that the wire would couple the roof
panels into a single ground plane.
The problem with this notion is that I have no quantitative idea whether
there is enough coupling at 3.5-30 MHz to make this useful. The antenna
seems to work fairly well, for what it is, but I don't have a field
strength meter I can use for comparative measurements.
Can anyone out there advise me? Am I simply barking up the wrong tree? If
not, would there be any percentage in adding one more wire, similarly but
differently laid out, for some additional coupling?
73, Pete N4ZR
The World HF Contest Station Database was updated 1 Feb 03.
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