Here is how (pictures and description) I installed my HD70 tower,
starting with the hole for the foundation. Most of what you asked
about is shown on pages 4 and 5, but if you are assembling the tower
yourself the entire series of pages may be useful to you.
I used Cadweld molds that I found on eBay to connect the ground wires to
the rebar, to connect the rebar to each other, and to connect the wires
to the tower base inside the foundation, but to be honest some of that
was probably overkill. My website doesn't show a picture of it, but my
ground wires also connect to each leg of the tower itself above the
foundation (which I did partly to be able to show later that the tower
was actually grounded), and for that I used half of a galvanized pipe
ground clamp (also bought at Home Depot). I drilled two holes through
the tower leg and bolted the half with the wire connection to the tower,
and after I tightened down the screw for the wire I sprayed everything
with galvanizing paint. I'm pretty sure that same method would work for
the wires that connect the rebar cage to the tower base inside the
foundation instead of using a wire-to-plate cadweld mold like I did. I
can take a picture and send it to you if my description here wasn't clear.
Here is how I grounded my coax at the top and bottom of the tower. I
bought the angle stock with holes in it from Home Depot and reamed out
the holes to fit 2 inch long nickle-plated SO-239 barrel connectors.
The picture shows the bracket at the bottom of the tower, but there is
also one at the top.
The picture at the bottom of the page shows the bracket at the bottom of
the tower, but there is also an identical bracket at the top. In fact,
I also put a smaller but similar bracket on each boom-to-mast plate in
order to make it easier to disconnect the antennas since the coax
attachments are pretty far out on the booms. You can see a picture of
that on page 2.
Lastly, I connected a 4/0 stranded wire between the mast and the top of
the tower (wrapped a couple of times around the mast to allow for
turning) because I didn't want to trust the top "thrust bearing"
(actually a bearing for lateral mast load) to keep lightning strikes
away from my rotator.
You will LOVE your HD60. I get monstrous wind gusts at my QTH on the
southern end of the Huachuca Mountains here in southern Arizona,
especially in the spring when the thermals are active. I've measured
clear sky wind gusts in excess of 95 mph, and 70 mph and 80 mph happen
several times almost every day in April and May. The tower with two
fairly large antennas (Optibeam OB16-3 and OB2-40) has held up
beautifully and I have a hard time seeing any deflection in such winds
when I stand at the base and look upwards. I'm actually afraid of
heights, but I've been at the top of my tower when 50 and 60 mph gusts
have hit it and can barely feel the sway. I've always felt secure up
there, although wearing a full body harness and being clamped in with
three different straps definitely helps that. ;) Your HD60 is of
course even stronger than my HD70.
Don't hesitate to ask if you have more questions.
On 9/16/2012 5:50 AM, Mat Eshpeter wrote:
I will be ordering an HD60 from AN Wireless on Monday for my windy and
lightning-prone ridge top WV location and have some questions regarding
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.
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
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:
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; and I need to figure out how
to make a solid connection of the ground wire to the tower legs. I have no idea
how to make this connection.
Thanks for any advice.MatKK1C
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