On Tue, 15 Jul 1997 13:59:11 -0400 (EDT) Pat Masterson <bat@grumman.com>
writes:
> I acquired a 5 section (40') tower from an SK estate. A TH6 came my
>way thru another source. The lower section of the tower is the 26" size.
>I'd like to add 2 more 26"s at the bottom, to get 56' of tower on top
of
>the 4' steel cage base. The top section is the 18" one.
>
============
I have two Heights 72-foot aluminum free-standing tilt-over towers, up
here since 1976. The configuration of the 9 eight-foot sections (from
bottom to top) is: 26", 26", 22", hinge, 22", 22", 18", 18", 18", 14".
Heights rated them (unguyed) with a projected antenna surface area of
26 sq ft @ 80mph, 22 sq ft @ 90 mph, 18 sq ft @ 100 mph, and 14 sq ft @
115 mph. The tower you have is the same as the top four sections of
Heights' model A80, which had the same wind load rating as my towers.
I've never had more antenna than a TH6DXX on one tower, and a 402BA on
the other (both still in place, used mostly as top-loaders for 160m), and
they have withstood 80+ mph winds unguyed many times over the years, most
recently on two occasions this past winter. However, I wouldn't trust
them with a much larger array on them without guys. (In fact, I just
guyed them last week at the 56-foot level for fear of metal fatigue after
21 years of swaying in the wind.)
=============
> I live on Long Island (Suffolk County) and was wondering if this kind
>of tower configuration can handle a TH6 here; and what size concrete
base
>I need to have to hold it up and meet specs. The literature I got from
>Heights has no mention of base size requirements.
>
=========
Heights never specified the concrete base size for your screw- or
winch- operated 4-foot high hinged base (which they did make), but they
did specify 4 cu yds for an HB-26, which is the same base, but 6 feet
high. The concrete bases for my towers, BTW, are 7' x 7' x 3.5' deep,
about 6.35 cu yds.
I hinged my towers at the 24-foot level (Acme screw-operated from the
ground), rather than at the four-foot level like yours, BTW. If you add
sections to the tower I suggest you do the same, because it'll be much
easier to crank over and back up again, especially with the weight of an
antenna at the top.
I'm wondering where you'll get the tower sections and other Heights
hardware you might need? I understand that Heights went out of business
years ago when the owner died and his son decided not to carry on.
Another who makes aluminum towers, Universal, makes only 10-foot sections
which are not compatible with Heights sections. I called them once a few
years back when I was considering going higher and they said they could
custom-build 8-foot sections for me if I sent them a template of the
tower section legs so that they could make a match. As I recall, they
wanted $450 for an 8-foot section of 18" on a side, which seemed a bit
steep for me, so I declined. (The towers cost me about $750 each
complete in 1976, and I guess I'm still accustomed to those prices!!)
Before you erect your tower, be sure to drill weep holes in the bottom
of the bottom-most section. In winter the water can freeze and split the
legs if water gets trapped in them. I had this sad experience early on
and had to replace a section in each tower.
My Heights towers have served me well over the years. The only other
refurbishment I have done was to take them down last fall (a one-man job
with the tilt-over feature) and replace all of the rusty nuts and bolts.
Additionally, I paint the steel parts (hinge, etc) every few years to
prevent rust.
This is my kind of tower -- lightweight, all assembled on the ground,
and no climbing!!
If you need more info, don't hesitate to ask.
73 es DX, de Earl, K6SE
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