Hi Mike,
Something seem wrong with your area numbers for the beams
you are planning to use. I have not seen the Force 12
literature on those antennas, but I know an average 20 meter
element has about 2 square feet. I believe a 40 meter
element would have somewhat more than twice that (full size)
so a full size three element 40 meter beam on a 30 foot boom
should have about 15 square feet of wind area. I'd double
check those figures . . . In fact, if those ARE Force 12
numbers, I'd recalculate them myself to make sure I agree
with them.
Stan w7ni@teleport.com
Mike A. King wrote:
> Hello fellow hams,
>
> I am considering the following Force 12 yagis and a
> boomer. Would like your
> comments on them one way or another. If you can comment
> on one, or all, any
> are appreciated. Comments on the tower are appreciated as
> well.
>
> MAG340 at 56'
> (30' boom 3 ele 40M beam - 6 Sqr Ft)
>
> MAG810 at 62'
> (30' boom 8 ele 10M beam - 4.2 Sqr Ft)
>
> EF906 at 67'
> (30' boom 9 ele 6M beam - 3.4 Sqr Ft)
>
> and a 17B2 Cushcraft Boomer at 72'
> (31' boom - 17 ele 2M beam - 3.9 Sqr Ft)
>
> Total Sqr Ft = 17.5 + 1 for the mast = 18.5 Sqr Ft Total
>
> I was going to put them on my soon to be installed HDX-555
> with 20' Cromaly
> mast. This tower is rated for 30 Sqr Ft at 50MPH and 1'
> above the tower. I
> belive it is rated for 23 Sqr ft at 70MPH
>
> Planning on a a yasue G1000SDX rotor, 23 Sqr Ft. Assuming
> 3' of the CM-20
> mast within the tower.
>
> Or could I practically put the 10M beam at the top? What
> about the MAG340?
>
> What do you experienced tower and yagi folks out there
> have to say? This is
> my first tower and I could use a little insight. The base
> is poured and
> ready for the tower to be delivered on Jan 1, so I need to
> get going on these
> antennas.
>
> Thanks to all of you in advance!
>
> Mike - KM0T scsueepe@mtcnet.net
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