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[TowerTalk] RE: Source for antenna masts......

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Subject: [TowerTalk] RE: Source for antenna masts......
From: aa4lr@arrl.net (Bill Coleman)
Date: Thu, 26 Jul 2001 14:51:07 -0400
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: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
            -- Wilbur Wright, 1901




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