[Elecraft] Need advice on Small Tower

[Robert Dorchuck]

Hi Mike,
I don't know where the 3 SQ-FT comes from.  US Tower does not publish ratings for the MA series any longer.  I have had an MA-40 since 1982 and at that time the rating was 10 SQ-FT @ 50 MPH winds fully extended.  I have confirmed this with US Tower in the past. I was also told at that time that they do not rate the tower retracted.  There have been some new regulations concerning tower ratings in the past couple which is probably why they do not list it now.  I have had a 3 Element SteppIR on this tower since 2006. The HRO website still lists the rating at 10 SQ-FT.
  

That being said, I do retract the tower if winds of 50 MPH are predicted or if I am leaving for any length of time.  My base is 3 X 3 X 5 which was recommended at that time and I have the drawings for that.

I think the 3 SQ is indicating the size of the extended portion which is 3 inches square.




Date: Wed, 13 Jul 2016 04:01:47 -0700 (MST)
From: Mike K2MK<k2mk at comcast.net>
To:elecraft at mailman.qth.net
Subject: Re: [Elecraft] Need advice on Small Tower
Message-ID:<1468407707184-7620050.post at n2.nabble.com>
Content-Type: text/plain; charset=us-ascii

Hi Terry,

I'm moving and I've just sold my MA40 with the MARB40 tilt over/rotator
base. It's a fine tower for small loads. Be careful, it's only rated at
3sqft load when the tower is cranked down to the 21 foot level. I had a 2
element SteppIR yagi on it and I would crank it down if winds over 20 or 30
mph were forecasted.

Cranking it up and down is very easy on the arm. It cranks easily but
requires 100 cranks. Tilting it over and cranking it down and back up
requires much greater effort until the mast is at the 45 degree angle. I
would have liked to have a power driven winch for that operation.

The foundation for this mast is substantial with lots of rebar. I'm selling
my house and just had the top 12" of concrete removed so that I could
replace it with grass. It took a crew longer to remove the 12" then it did
for the crew to dig and pour the foundation in the first place. I'm thankful
I didn't have to any of the work.

This mast can actually be handled by one person if you have moderate
equipment to help. I had a wheeled lawn cart for rolling it around and a
Harbor Freight 1 ton shop crane for taking it off of the flat bed delivery
truck and helping to engage and dis-engage the mast into the MRB40 unit.
With two people it's a very simple job. All of my experiences were good and
given the opportunity I would not hesitate to purchase another one.

I have a personal website with lots of photos. Contact me directly if you
want the link.
k2mk at comcast dot net

73,
Mike K2MK