[TowerTalk] Top Loading Question..

[David Douglass]

Hi Guy's,

I'm looking at replacing my current 80M vertical antenna (10m high wire,
centre loaded on a DK9SQ telescopic fibreglass pole), with a top loaded
vertical (2x20foot aluminium poles).

Is there a calculation I can use for working out the inductance of the coil
I'll need at the top, or is it easier just going by trial and error ??

I've also been thinking about the possibility of a vertical dipole (similar
to the Force 12 Sigma-80 type antenna), as I don't have enough room for a
full radial screen, and currently just use 2x20m radials along the fence
line at about 4 foot. Does anyone have any experience with this type of
antenna, or know of some links on the net, etc etc..

Thanks in advance

David, VK2DPD