> Long ago I picked up a (hefty) 80-meter trap, intended for a 160/80
> meter dipole. I'm thinking of inserting it in the horizontal wire with
> some appropriate trimming to provide coverage on both bands. Am I missing
> something fundamental here? I've not seen this described in the magazines
> or books, but it seems like a reasonable configuration. Too much loss in
> the trap? Won't work at all? 73,
Hi Jeff,
The only catch is the power rating of the trap will be approximately
half the rating of what it is in a dipole. That is because current and
voltage in your Marconi antenna across and through the trap are
about twice that of a dipole.
On 160 meters, the trap in a marconi sees about 1.41 times the
current in a dipole so I^2 R heating will be about twice as much
(heating is the problem where the trap operates straight through).
On 80 meters there will be about 1.41 times the voltage, so power
rating will be reduce by the square of 1.41.
When the antenna is folded in an L this stuff actually gets a little
worse.
Other than the potential power rating problem, everything else is a
winner.
73, Tom W8JI
w8ji@contesting.com
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