My first crank-up and tilt over tower was an EZ-Way. I bought it second
hand when I was 18 years old and deposited in my parents backyard. Some
years later when I was living in a home of my own, I went to move it and
found the wonder post to be rusted so much that a screwdriver could
easily puncture it. I had a welder/ham buddy of mine fabricate a new
wonder post for me with over sized missile fins. I dropped it in the
sandy Florida soil for the second time since I'd owned it and it worked
well for a number of years until near hurricane force winds and rain
pounded it for the better part of a day. When the wind and rain had
stopped there was a considerable lean to the post and tower. To look at
the soil surrounding the post, you'd think that the it had never been
disturbed. The tower and post endured hours of rocking in the wind -
principally in one direction. The repeated oscillation had caused the
soil on one side of the wonder post (direction of wind travel) to snow
plow out of the way while the soil behind the post immediately back
filled with the driving rains.
After removing the tower and straightening up the pole, I added a 3' by
3' by 1' deep slab to act as a 'table top' of sorts around the top of
the wonder post. It continued to work for years until I removed and
replaced it with a TX-455.
Oscillation can be a terrible thing.
73,
Jon Pearl - W4ABC
www.w4abc.com
> 49 years ago I helped do an EZway tower with the "Wonder Ground Post",
> rocket fins on the bottom of the post.
>
> The owner (one of them engineers) did the math for a round disk, 3' in
> diameter, 4" thick of concrete flush with ground level, not sticking to
> the post.
>
> He came up with some considerable multiplication of tilt over forces,
> which I forgot, 48 years ago.
>
> Someone with a bigger brain might try to apply the idea to the guy posts
> and let us know some numbers.
>
>
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