Hello Kim:

 

I just finished a meeting with our engineers. We will be designing a heavy duty mount for your new Skyhawk. It will use our Super Duty clamps. The plate will use 8 of these: https://www.dxengineering.com/parts/dxe-hds-200ap  and the plate will look like one I built for K3LR last week. I think this will be fine. What size mast are you using?

 

 

 

Hi Tim,

The Alpha Signa Delta Radio Society (the official name of the OU amateur radio club) has received a grant from the ARDC for new equipment. Chief among the items the club will purchase is a new Skyhawk 3X10 to replace the one that came down. We have yet to retrieve what's left of the mounting hardware still on the mast, but that's one of the items paid for by the grant.

We expect to find no fault in the installation or the hardware itself, but even so we *must* to insure that another one simply will *not* come down again. When this one fell a surprising amount of damage was done to the roof of the NWC that was found only later when the leaks became serious. What can DXEngineering do to strengthen the mounting system? From what we've seen so far, it appears that the U-bolts fatigued and ultimately failed. Can they be made larger and out of a stronger material? We've become pretty sure that because of the nature of the building there is extreme turbulence at the antenna height consisting of eddies that are on the scale of the antenna itself. We originally had a 3 el SteppIR up there that was completely destroyed by the turbulence at the antenna height. Eddies on the scale of the antenna itself are probably the worst possible combination from a structural standpoint. It's up just short of 200 ft and so the wind for the most part never stops up there and there's quite a vertical gradient in the wind speed from ground level up to the top of the building, especially at night.

When we put up the new antenna, we'll use the permanent (red) LocTite on all the hardware (we used the blue stuff last time) and we'll require the tower crew to provide photographic evidence that it was applied. What can DXE do to make the mount stronger for our application?

73,

Kim N5OP