I have a lot of experience at K0RF's station where various HFantennas at
strategic heights perform differently depending on conditions. Spending a
weekend at a world class M/M contest station with several various monobanders
teaches one that incoming angle can vary and therefore, lower antennas work
better for certain circumstances than higher antennas.
That said, my stack of log periodics, using identical antennas, one at 42
feet, one at 75 feet, shows the higher antenna out performs the lower antenna
on most occasions with few exceptions pertaining to higher than normal angle
RF. I was glad I went from a single antenna at 55 feet, to raising the tower
another 20 feet to put it at 75 feet. In my case, I feel the 20 additional
feet made a significant difference and was well worth it- But I'm not sure
if going from 75 feet to 95 feet would matter a whole lot as there is a
diminishing return based on a number of reports I've read and heard of over
the years.
I would think that most hams, with typical back yard set ups, should attempt
to put their HF antennas at the maximum height where safety, legalities,
reasonableness, and finances allow. A thought echoed by many others already
responding to this subject.
While on Lord Howe in April of 1998, my Force 12 12/17 dual bander worked
great on a 15 foot wooden mast if that's worth anything. All because you
can't put up an antenna at 70 feet, doesn't mean you should be discouraged
from using beams. Safety first, a beam mounted low can still be a lot of
fun- Just look at all the field day set ups!
73 Paul N0AH ex VK9LZ
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
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