I was looking at the engineering drawing for Rohn 25G yesterday, and was
surprised to see that the total length of a section is 10' 0". This
*includes* the 3.5" that is inserted into the next section. The
effective height of a 10' section is only 9' 8.5". While not significant
for one section, it quickly adds up on a tall tower.
I wondered if this was possibly an error on the drawing, so I went out
to my tower and took a measurement. Sure enough, the distance from the
bottom of the first section to the bottom of the second section is 9' 8.5".
And here I've been thinking for years that my Rohn 25G-FK-68 tower was
really 68' tall, when it's actually only 66' 3". I would call this a
"truth in advertising" problem!
73, John, K9MM
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