> 1. It looks like the preferred way to support the base prior
> to concrete is to rest the base on cinder blocks. Are there
> other tricks needed to keep the base level and immobile
> during the actual concrete pour? Perhaps I need to use rebar
> ties to fasten the tower base to the rebar cage? I am
> paranoid about having the base shift during the pour and
> creating a "leaning tower of Pisa" in my yard.
You should check with whoever issued your building permit to see what they
want you to use. I've run into many inspectors who didn't want to see any
kind of foreign material/items in the foundation. I've had to pull up
entire rebar cages for some rather large tower foundations and guy anchors
due to the contractor having used impermissible blocks to elevate the cage
off the floor of the hole.
Obviously you'll want to guy the tower to keep it stable during the pour and
cure. That should allow for adequate adjustment of the plumb should the
base shift a bit during the pour.
> 2. How did you run your feedline up the tower -- are there
> suitable clamps available? The profile of the legs looks
> makes me think some ingenuity will be needed.
Stainless angle member adapters (aka "beam clamps") and the appropriate
hangers or hanger brackets.
> 3. Grounding coax at top of tower - Same tower leg profile
> challenge. I have only found products that are suitable for
> tubular shaped tower legs. So how do you securely bond the
> shield to the tower leg of an AN Wireless tower? Example:
While not explicitly designed for it, on commercial towers it's not uncommon
to use stainless angle member adapters as the interface between angular
tower members and the lugs on the end of the ground kits.
I'd recommend using real ground kits over those "grounding brackets" made by
DXE and others that rely on the RF connector to provide the interface
between the coax shield and the tower.
> 4. Grounding base of tower to ground field - I have 2/0 solid
> copper that I need to connect to the tower legs at the base.
> Same tower leg profile challenge. The tower is galvanized so
> I need some sort of stainless steel plate to separate the
> galvanized tower from the copper
I always avoid mechanical ground connections for the primary grounding
conductors - cadweld the conductors to the legs.
--- Jeff WN3A
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