I'm with Gary on this one - and ON4UN. Making inverted L and better yet
T-top loaded verticals too long will raise the maximum current off the
ground and reduce the current in the ground system - both good things.
My T-vertical here is resonant at 1.2 MHz and tuned out with an L
network that can be calculated with TLW software with just a few minutes
The "too long" antenna can be built as Gary mentions with a simple
series capacitance, or for a better match an L network. Mine components
are exposed to the weather - I see no reason to lower their Q by putting
them in a box. They have been outdoors for five years and run at 1.5 KW
in the rain just fine.
Per Jay's article, a high pass arrangement is nice if you have severe
BCB interference - otherwise I would head the other way, to a longer
antenna. Also, there are other ways to deal with BCB interference than
making the antenna otherwise too short.
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