> Trees are not ideal antenna supports because it is not
> easy keeping the wire
> away from branches. This autumn my inverted 'L' gradually
> moved it's
> resonant frequency up the band by about 20 KHz as the
> leaves dropped off the
> deciduous tree supporting it! I spent today moving the
> antenna away from the
> tree - I've lost a little in height but see an immediate
> improvement in feed
> impedance which has dropped significantly.
That is interesting.
The NW element of my four square always measured slightly
higher in feed impedance than the other three elements. That
element was about 50 feet or less from three large Pecan
trees, maybe 60-70 feet tall. When two of the trees were
sentenced to death for dropping leaves in my wife's swimming
pool the feed impedance dropped a little.
I always wondered how many other trees seemed to affect
impedance, even when they were not touching the element.
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