On 7/26/01 1:11 AM, K7LXC@aol.com at K7LXC@aol.com wrote:
> As always: what's your county windspeed rating and how far above the top
>of the tower will the antenna be?
> For an 80 MPH and below and the antenna is within one-foot of the top of
>the tower, go to Home Depot or anyplace that's got 1.5" waterpipe or
>conduit. That's FB for this application.
The only problem with 1.5" waterpipe or rigid conduit is that it doesn't
make a great fit for the mountings designed for 2" masting.
I have my R7000 mounted on 1.5" rigid conduit (not to be confused with
EMT). The U-bolt saddles do not fit well around the conduit, and I had to
develop some shims out of 1.5" PVC to get the antenna to sit straight.
If you use a 1.5" conduit with a thrust bearing, you will encounter axis
errors between the rotator and bearing, unless you carefully shim the
rotator. Even so, the U-bolt saddles on the beam may not fit well.
That said, I came up with a low-cost way to obtain a mast -- I put out a
call to my local ham buddies. A quick e-mail on the local contesters list
produced three sources for a short (5-9') 2" mast. A local ham was happy
to supply me with an Al mast at a price that can't be beat.
So, look around. Someone may have a 20 foot bent mast that can be
salvaged to produce a good 5-10 foot section in your area.
Bill Coleman, AA4LR, PP-ASEL Mail: firstname.lastname@example.org
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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