I had my 3 el SteppIR at various heights, in VT, on a military
pushup mast. 30, 50, 65, 80, 100'. It wasn't dynamically adjustable,
and it was now two seasons ago, so there was more sun to play with.
However, in general, having the antenna a full wavelength above ground
improved performance on long distance contacts substantially.
Pretty much as you would expect, dx went up 10-20 dB and stateside went
down by the same.
Here in Suburbia, I'm condemned to stealth antennas, and an MA550 with
10' of top mast (65')is the hoist of choice. It'll stow behind my roofline
when not in use, and I can motorize it to appropriate heights for each
I would assume that during times of high sunspot activity, as Bill (?) said,
higher angles would be supported by the ionosphere, and a lower antenna
be better. I know during the peaks we had a 10m yagi at W3GM's for contests
which was at 20'. At mid day, it outperformed stacks to 100'.
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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