In a message dated 00-01-04 08:40:48 EST, ON7YD writes:
<< Basicaly a 'top inductance' reduces the voltage on the vertical part of the
antenna. Assuming that the losses induced in surrounding objects (ground,
houses, trees, etc...) affect mainly the electrical field this could mean
that by reducing the voltage on the vertical section also the losses caused
by this section are reduced. >>
For what it's worth, this does seem consistent with results at my location.
Although I probably don't have quite as many trees in the immediate vicinity,
I found that for a given antenna current, my radiated signal on 1750 meters
was appreciably better after moving some of the inductance above the ground
and thereby reducing voltage on the vertical run of the antenna. (It also
has the welcome side-effect of less chance of accidental RF burns.)
73,
John KD4IDY
|
