[TowerTalk] 3el on 80m with another antenna?

[Scott W3TX]

Hi Gia,

With regard to colocating 80m and other band antennas: Several years ago I 
had a similar discussion with Mike Stahl at M2 and did some extensive 
modeling with Al Christman K3LC.

The general finding is that there are very significant interactions between 
the 80m and 20m horizontal elements.  The interactions were enough for me to 
re-consider colocating 80m and 20m yagis. Also, I would be concerned about 
colocating 80m and 40m yagis.

If land space is available I would recommend pursuing a 4-square or 9-circle 
on 80m.  These antennas, with a good radial system, will be superior at the 
important low elevation angles compared to an 80m horizontal array at 100ft. 
The difference between vertical and horizontal polarization will reduce 
interactions to some degree.

If land space is not available then one could consider placing the 80 and 
20m arrays on different towers.

73, Scott W3TX