it is on a rohn 25g at a total height of 60 ft. i use 3 sets of guys @ 20'
40' and the top at 60'......i know that is overly cautious but i was unable to
spread guys to 60% of the height....my antennas are:
cushcraft 13b3 1.8sq/ft 68'
cushcraft 6176b 4.8sq/ft 60'
cushcraft 719b 1.2sq/ft 65'
2-2m big wheel 1.0sq/ft (apx) 55'
2-6m loop 1.0sq/ft (apx) 55'
2-70cm loops 0.4sq/ft (apx) 55'
10m sloping dipole 0.2sq/ft (est) 50'
40-20-15-10m dipole 0.5sq/ft (est) 50'
80m inverted vee 0.8sq/ft (est) 55'
discone scanner ant 0.5sq/ft (est) 45'
12.2sq/ft apx
1-7/8" hardline
2-1/2" hardline
3-RG-213
1-RG-8X
1-remote coax switch @55'
my 235lb fat butt (sometimes)
Rohn gives 10.2sq/ft at the 60' level with 2 sets of guys at 55' and 28'
levels and allows 1 5/8" feed line on each leg for 90mph wind velocity and no
ice.
if i assume the maximum, then i have exceeded the design, however, i expect
the dipoles to fail with 1/2" ice and therefore reduce the total top load to
10.7sq/ft. still puts me 0.5sq/ft over the allowable max top antenna load but
there is 2.4sq/ft at the 55' level and 0.5sq/ft at the 45' level......I am
pretty sure i am in the ball park area of having a safe tower installation.
de kd5qwo, david howard
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See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
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