Feel free to post your callsign
Windload is a complicated subject as I'm sure you know. I am not familiar
with either of these towers however the windload specs for the US tower are
worse than what you posted for Hy-Gain.
Weight 350#
Exposure C windload 11sqft
If you do intend to switch towers at a later date it, I would recommend to
install the base so it's suitable for both towers. It's easier than
drilling and epoxying anchor bolts later or worse having to re-excavate.
GL
John KK9A
From: "Dave ." <ktx85@hotmail.com>
Wow....
I live in central Iowa.....Originally was planning on a US tower
Hdx70 tower but it was destroyed in bad weather before I could
purchase....so
this Hy Gain tower became avaliable..I thought I could use this for now
until I
got a 70 replacement...but
Confusion ...
I was looking up a HyGain hg54HD
IN one factory document I see 16sq ft at 60mph (1990)
In annother factory calculations document I see 25sq ft
I know these calculations are from days of old
And other mfg numbers are ALL over the place
And let's not forget that many of the antenna mfg windload numbers are
well...I'm not sure what to call them
Here is the plan
HY-54GD....16sq....supports ?
Concrete base for tower is rated for a HDX70 ( 2 x more Concrete than the
hy54hd requires)
For comparison
Hdx555 23 Sq. Supports 200lbs
nn4zz tiltplate......1sq. 30lbs
Steppir 4 El 40-6....( 1 trombone)........18.5 Sq. PROJECTED ??? A few
sites
say 12sq......106lbs
3 .....M2. 2m12 2m yagi. 1.5 Sq each. 8lbs each
1 wire dipole......
1 diamond x510HMN..........
Yaesu 2800 rotator...14.33 lbs
2 inch 1/4 wall 6063 alum mast...4 1/2 foot above the Tilt plate...Tilt
plate 2
inches above thrust bearing
Looks like my wind load with all the above would be 23.5 sq....OOPS...
OBVIOUSLY...I wouldn't leave the tower up in a 60mph wind.( that's asking
for
trouble)
It is 22ft cranked all the way down.....
It seems as if you want more than a dipole on top you have to purchase a
80,000
tower
Are there numbers SOMEWHERE that are "real" .?
Every mfg seems to have their own calculator..
M2 antennas and nn4zz seem reasonable
It appears all numbers are cover your butt numbers the mfg have come up
with...
There are so many years and years of politics in between. And
calculators....
And to say hams NEVER overload their towers....well...that would be a
fairytale
Is there some rule of thumb that this might work to say 30-40 mph without
cranking down?....is there someone with a simular set up that is in use that
can share some thoughts ?
Sigh
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