>>There is NO SINGLE OPTIMUM HEIGHT, especially for the high bands. TWO
>>antennas at 40 and 80 ft are very effective with
>>switching for upper, lower, and both in phase.
>I aggree with your comments but, to ask the orignal question again.
>If I gave you a TH-7 and this was to be your only antenna
>for 20-15-10 and you wanted it to work "best" over an
>entire solar cycle at anytime of day or at any distance
>at what height would you put it?
>George Fremin III
I believe that most tribanders are "modeled" for a height of between 50 and
70 feet so the simple answer would be to put it between those two heights;
and most amateurs will put it as high as the wallet will allow. But it gets
a lot more complicated, as N6BV points out in "All The Right Angles". If
your tower sits atop a hill with steep drops to all sides than 50' is
probably going to be too high...especially on 10M. On the other hand if you
are surrounded by hills than 70' is too low.
Get a copy of YTAD from the ARRL BBS and run different plots for your own
terrain. And if you have the ARRL Antenna book use the elevation files that
are on the included disk. These files were compiled from statistics
covering an entire 11 year cycle.
BTW, my TH6 is at 50' 'cause that's all the tower I have!
Doug - K1ZO
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