[TowerTalk] Crankup Tower for DB-36

[John Kuklewicz N7ZN]

Well, after many years of wishing, it looks like 2012 will be the year I 
finally get a tower and yagi added to my station. After many years with 
multi-band verticals and relatively low wires this is a much anticipated 
enhancement. More than likely with will be the one and only tower I will 
be able to install.

I do not have any experience with towers, and would value your inputs on 
my thinking below.

I would very much like to install a Steppir DB-36 on a tower of at least 
70 feet. I know, higher would be better, but the next increment in 
height seems to entail a disproportionate increase in cost. After all 
these years, I really would like to have gain antennas on 40 and 30 
meters. Per Steppir, the DB36 is 17.5 sq ft, 160 lbs.

After a lot of soul searching, I have to admit that I am in no shape to 
be climbing towers, and this is not likely to change. And there is not a 
strong local climbing ham population to assist.

So, a crankup/tiltover tower (with NN4ZZ tiltplate) seems to be the only 
solution. The only towers that look even close are the US Tower HDX-572 
or the Tashjian DX-70.

I am fortunate to live in a rural area with no zoning or permitting 
requirements. I can put up any foolish thing I want. <grin>

Today I was able to obtain an engineering analysis for the HDX-572 and 
was disappointed to learn that the Windload is limited to 14.1 sq ft 
(exposure B, 90 mph 3 second gust, 76mph fastest mile.)

The Tashjian DX-70 shows a spec of 47 sq ft (85 mph 3 second gust). 
Clearly this will be adequate (if not somewhat over designed - which is 
not a bad thing). Of course, the DX-70 initial quote I have about $1K 
more than the HDX-572. IT would certainly seem that the increased 
capacity is worth the greater initial expense.

Can anyone help by contributing their experience with a DB36 (or similar 
large antennas) on a crankup in the 70 foot (or taller) class?

Many thanks and 73;

John N7ZN