Chris,
You may be much happier, since you have 40 acres, putting up two towers.
In addition to being less expensive than some of the options suggested,
interaction will not be a problem, mast material is no problem, flexibility in
turning antennas in different directions will be a plus, and rotators will be
easier to deal with and less expensive. If you were to try to turn what you
mentioned with anything less than a prop pitch you may have issues. You will
also have the flexibility of having the antennas at different heights, if you
want.
One thing to consider is whether there will be any wind load on a tower a few
seconds after a 110 mph wind hits it. I would bet that the towers will be
there and the antennas, well not so much. Yes, in reality these towers will
handle a lot more than their ratings would indicate.
If it were me, I would consider 55G for the 40m antenna and 45G for the multi
bander or better yet, for ease of maintenance and plenty of headroom on specs,
a 65G rotating tower. That will handle a lot of antenna and the rotator is at
ground level.
73... Stan, K5GO
> On Apr 3, 2016, at 7:21 PM, Chris Hoelzle <choelzle@cox.net> wrote:
>
> Hello - I am intending on putting up a tower at my new home in Bandon, Or. I
> have 40 acres and it is surrounded with 70 foot high timber. When I saw the
> layout and I thought I would put up a 150ft tower. I will not be doing this
> often, so I want to put it up once and have it stand. General TIA wind
> ratings for the county are 80mph, with "special areas" - and of course I am
> in one of those special areas which has ratings of 110mph.
>
>
>
> Right off the bat I excluded putting up a Rohn 25G, opting instead for a 45G
> - but then a buddy of mine said that he would go for a 55g.
>
>
>
> I intend on putting up a big M2 or Mosley multi-bander (15sqft) and a 40
> meter three element (20 sqft).
>
>
>
> I know of folks that have these sorts of setups, but when I take a look at
> the Rohn wind load I was really surprised.
>
>
>
> A Rohn 45 150 foot 130mph rev G / 110 mph Rev F shows it will only allow
> 10.4 sqft of load.
>
>
>
> So, I thought a Rohn 55 would do the trick but it shows:
>
>
>
> Rohn 55 150 foot 130mph rev G / 110 mph Rev F shows it will only allow 16.6
> sqft of load.
>
>
>
> Are the specs WAY too conservative or should I put up a really HUGE tower to
> accommodate what I want to do?
>
>
>
> Any thoughts on my conundrum would be greatly appreciated.
>
>
>
>
>
> NN6CH
>
> Chris Hoelzle
> choelzle@cox.net
> Laguna Niguel, CA
>
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>
>
>
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