[Towertalk] Antenna Spacing on New Tower

[K7LXC@aol.com]

In a message dated 11/8/02 7:19:46 PM Pacific Standard Time, 
sunset392@cox.net writes:

> I will be installing a US Tower TX-489 and planning to install the following
>  antennas
>  
>  
>  1. New KLM 10-30-7 LPA 1' above the tower (30' Boom & 8.25 sq ft)
>  2. Hy-gain Discoverer 7-2  40 Meter 2-element Beam ( 22.6' Boom & 6.0 sq 
ft)
>  above that
>  3. Diamond 500HNA 144/440 vertical (17.8') on top
>  
>  
>   I have a 6061-T6 2" x 24' aluminum mast and my question is what spacing is
>  needed to insure no interaction between antennas and should the beams be
>  rotated 90 degrees to each other or could I keep them in the same
>  orientation.

    Okay, let's get a little more basic. What's your county windspeed rating? 
If you don't know, you can look it up at  <A 
HREF="http://www.championradio.com">www.championradio.com</A> under Tech 
Notes. 

    I suspect that your aluminum mast (35,000 psi yield strength) isn't up to 
the task. For example at 70 MPH with a ten-foot spacing between the LP at the 
bottom and the 40M 10 feet up needs a mast with 50,000 psi yield strength.

Cheers,
Steve    K7LXC