[PVRCNC] Rohn 25G - how many beams?

[KI7WX at aol.com]

Brad,

25G is reasonably stout tower, but you'll be going into overload territory. The actual tower sections are only a fraction of a guyed tower's cost, so my advice would be to go to something that will really work for you. You'll be happier in the long run and it'll be safer. 

If you'd like to see what happens to 25G when it gets crushed by a tree, ask Bob, K4HA, to show you the tower fragment from my old place. 25G was never meant to resist falling pine trees...

FWIW, even with my small feet I don't like to spend a lot of time on 25G tower. With the project you've outlined you'll be spending a lot of time on the tower so going to 45 or 55G will be useful just from a working perspective.

The phrasing of your message makes it appear that you expected this type of response and were already thinking about alternatives (e.g. AB105, 45G or 55G). If that is true, then I'd follow your gut instinct on this one.

For guy anchors, if you want elevated guys with I-beams look at either N3RR or the K4JA web sites for nice examples. For buried anchors just get the Rohn anchors and equilizer plates, and follow the directions in the Rohn catalog.

You didn't ask, but I'd reconsider your thinking on the tribanders. For my NC station I started down the tribander road, but after consultation with a number of folks that had built serious contest stations, I ended up doing one 115 foot 55G tower with a 40M yagi and a 20M stack, and then a shorter 25G tower with 10 and 15 meter yagis. I was extremely happy with that station. If I had to do it again I'd go slightly higher with the shorter tower (70 instead of 50 feet) but I always felt loud on 20 and 40 which was a big part of my design goal. As we go down the sunspot curve being loud on 20+40 will be even more necessary.

Hope that helps.

Mark
KI7WX/2