Hello-
I would like to hear opinions from some of the followers here regarding a
few topics on a planned 90' 45-G tower, down near Gulf Coast.I am installing
per Rohn specs using concrete guy anchors, 1/4" EHS and Preformed Big Grips.
1. I have always used the 2" ID tube top sections as they were convienant
when extending out a long mast.I plan to put up a TH7-DX just a few feet above
tower top and a 40 meter rotary dipole antenna above the TH7-DX, spaced maybe 8
feet or so. I am thinking of using the 45AG-4 flat top section with TB-3 thrust
bearing. Do you feel this is stronger as far as wind resistance? It sure
appears to me that the 45AG-4 with guy wires right at the outer edges of top
plate would be stronger.I believe in doing this I will need to use another
rotor shelf with an additional bearing or locking collar several feet below
flat-top in order to hold the extended mast straight.This setup is more costly
but seems worth it to me.
Speaking of the flat top section 45AG-4, is there any strength difference
between using it as compared to using a straight section coupled to the BPL-45G
flat top plate with TB-3 bearing? This seems like a trivial point, only
involving the 3 feet of heigth gained with using the latter, but when you look
at the BPL-45G it has the 1-5/8" sleeves welded to it as compared to the 45AG-4
having 1-1/4" legs welded to it.Maybe the extra cost of the combination is not
worth it?
2. I have always concreted base section in ground as it provided an easy
start in getting first few sections up before first guy level made.I believe I
am sold on using the concrete base plate { BPC-45G} and pier pin / bolt.Seems
like the described advantages of reduction in stresses at tower base, proper
drainage of legs are worth the trouble of using temporary guys.
3. Is there a treatice on using the guy equalizer plates? I was a little
uncomfortable in using the 3 hole ones on the last installation as the plates
cocked over when placing the lower guy, then adjusted some with middle guy, but
when top guys were installed the tension had to be re-adjusted on all. The
interaction of the 3 guys made adjusting tension more complicated. Is there a
reason for this? Is the equalizer plate performing a certain function? You
know, you can buy the guy anchors with a 3 or 5 hole plate welded to them. It
is fixed and won't move.How does using this type anchor plate compare to the
equalizing type I wonder, as far as tower effects?
Thank you all, Byron WA5THJ.
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