They don’t make things like they used to.

bubbablitz

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Feb 15, 2016
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This was in the local paper today, bent in half wth gusts of less than 50 MPH as per the NWS website.
There are a couple of towers in my neighborhood at homes that look like the original amateur operator is long gone (bent radials, broken off elements), but their tower is still standing. Cheap Chinese steel, poor construction, or maybe a combination of both? Any thoughts?

 

N5XPM

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Tower is too small to handle the wind load of the microwave dishes.
Flat Plate Wind load is a specification that needs to be understood and calculated before bolting things to communications towers.

The fiberglass omni might be salvageable however.
 

iMONITOR

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I would think if it was due to wind load on the dishes it would have bent somewhere below them. I'm wondering if they comprimised the mechanical strength of the antenna by damaging or weakening it at the point where they attached the dishes. It also looks like they also mounted a PTZ camera on some type of horizontal boom. May clamps crushed the tubing or they possibly drilled holes in it.
 

prcguy

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So Cal - Richardson, TX - Tewksbury, MA
That tower looks like 5 or 6 sections of light duty Rohn BX series, which is all sheet metal. Depending on the model and how fat the bottom section is, they can handle from 6 to 18sq ft of antenna area in a 70mhp wind. I never felt comfortable climbing those.
 

mmckenna

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We don't know the full story, so guessing...

But I've found no shortage of contractors that are "communications experts". We had a low voltage contractor (CAT5 wiring/Phone wiring) back in the day when we built our new PD/dispatch center. Said low voltage contractor had a ham radio operator on the install crew, and he was the "radio expert". Antenna masts were 2" rigid conduit stuck through a roof jack with a weather head on the top. The masts were held in with conduit straps and sheet rock screws. The LMR-400 they ran had poorly installed connectors. A lot of the work had to be redone.


From the looks of the coaxial cable flopping around freely inside the tower, I'd bet someone a cold beer it was a low bid tower installed by low bid electrical/low voltage contractor.
 
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