I wonder if anyone can offer opinions on the advantages that vertically
polarized antennas have over horizontals on 160M related to geomagnetic
Earth absortion?
I did a web search and see nothing on this subject related to polarization.
Might be looking in the wrong places.
I've been told by a good friend that a high horizontal is at a -10db deficit
right outa the box against a good vertical due to the natural Earth's
absorption on 160M and below..
I've know of one amateur who has an inv vee at 300'+ and says the vertical
out performs it for DX.
To prove it out, I put up a dipole at 198' broadside to Europe. I find the
3el vertical array is almost always 6-12 db louder for Eur. Locally, the
dipole is always better, of course.
Off the cuff, I would think the two antennas would be somewhat closer, as a
dipole at 3/8 wave high has some "reasonable" low angle components. And, the
horizontal dipole has an added 6 db ground reflection that the vertical
does not ??
On 75M it's the opposite. High horizontals outperform any vertical I've
tried by 10 db or more into Eur. The evidence seems to fit the absorption
idea for 160M. Though when I first heard about it I dismissed it as ham folk
lore hocus-pocus.
The opposite shows up in modeling. It appears that a two el yagi at a
"modest" 220' high on 160M would snuff a vertical four square... but I'm
sure the absorption is not being considered if it's truly an influence.
Anyone do similar tests or have ideas on the subject?
Tnx!
Tom, K1JJ
CT
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