Batboard

hello,
does anyone know if a rogh 25g needs to be guyed or not?
i've seen them self supporting .......whats the circumstances involved.
my senario is this :....60 ft tower in concrete base as per the instructions by rohn...also 23 feet up braced to the house via rohns house bracket.

do i need to still guy it
otto

I would have to dig up or download their spec sheets. How many feet do you have unsupported above the house bracket?

If i recall correctly the specs said that you could only go a max of 30 feet unguyed above the house bracket, and it won't be that fun to climb up to the top due to movement.

Rohn is by design a guyed tower, period. You CAN scrape by, "depending." I sure as heck wouldn't want to climb that thing. You've got some 40 ft "self supporting" assuming the house bracket is solid, and I mean solid.

Now it depends on what's on top (a two meter ground plane, maybe?) what the wind, the snow and ice load is in your area, and think about THIS

What would happen if it DID fall, could it hurt/kill anyone, fall on other peoples property?

I'd guy it , were it me, there isn't any other option, unless you want to install a free standing design.

Twenty feet of 25G, with an omni on top, maybe. anything taller........

thanks guys for your input.
i really have no way of guying it w/out goin onto neighbors property so i guess i'll put up the rohn bx tower i have and buy 1 or 2 more sections for it ......i know the bx is self supporting and i still plan on bracing it to the house.

thanks
otto

bayfire300 wrote:thanks guys for your input.
i really have no way of guying it w/out goin onto neighbors property so i guess i'll put up the rohn bx tower i have and buy 1 or 2 more sections for it ......i know the bx is self supporting and i still plan on bracing it to the house.

thanks
otto

I had a 32 foot Rohn HBX up for 4 years in New England
with a 3 band HF quad on it, no need to brace it to the
house. What do you plan to put up for antennas?

Peter
K2XM
The Rocky Coast of Maine

just 1 17 foot vertical antenna

for my repeater

otto

The answer you need is located on this page:

http://www.radiancorp.com/ROHNNET/rohnn ... index.html

Click on online catalog..then click on gt series tower.... then click on 25g... then click on bracket elevation.. You will need to know the square foot windload rating of your antenna. Does not cover partial guyed/bracketed installs but will give you an idea of what you can do.. Hope that helps a bit

ok thanks ........i appreciate all you help guys thank you

otto

Here's one of the Rohn 25G tower sites slated for replacement here this summer. Yup, it's not guyed. It's been up for over 20 years in some of the nastiest weather, all that's on top is a PD220 super stationmaster. A 60-foot SSV is its replacement, I feel much more comfortable climbing one of those... heh

I'm sure glad i'm not this guy, I swear the tower is bending the direction he's leaning...

Just because one guy gets away with it..........


I notice that it is bracketed up pretty high--which helps, but climbing, you are depending on the semi-might-just-be rotted 2x at the roof peak, not to mention whatever box nails someone might have used to hold the bracket.

I have no idea of the snow and ice, wind loads in your area.........

The area appears well shielded from direct wind by the trees.......

Just because YOU got away with it.........

I don't know about ya'll, but i sure as heck wouldn't be up on non-guyed 25G that far, yikes!!

I believe the base is 4'x4'x3' concrete and the house bracket is thru-bolted through the eave and attached to the peak beam, which is not rotted out (yet). This site is in a valley and is subject to snow, light ice loading, and 75mph winds.

I didn't mean to imply that such a tower is 'safe' or that it's an 'acceptable' example of an unguyed tower whatsoever, but it defiantely has lasted through the years. I'm just glad none of the antennas have needed work since i've been working here

At work our safety standards have changed in the past few years and because of this and the old age of the towers, they're being replaced with the SSV self-supporting towers, which include a steel cable grab climbing system and are much safer to climb (not to mention they don't wobble around as much at the top).

I wish I was an inspector, because my FIRST act would be to CONDEM this junk and if he wanted a tower, he would have to provide proper guying and base support......His 'base' was two feet square and three feet deep...no reinforcement, and no drainage!

Exactly. The towers in the outlying areas here were installed many years ago by someone who has since retired, and probably had a different opinion on what was required for the tower base specs. None of them have fallen, but that's besides the point. Tower safety and proper engineering is top priority. May not have been then, but it definately is now.

The new 60' Rohn SSV (self-supporting) towers we're replacing them with require 11.3 cubic yards of reenforced concrete for the SB5 base, which amounts to 8'9" square by 4' deep (tower manufacturer's specs). One of our older SSV tower sites is in an area that endures 90mph winds with about 2" of rime ice each winter, it's been inspected annually for the last 15 years with no problems.