Remember, Power and telephone poles are guyed at the top in opposing
directions (180 degrees).
In the old days, I climbed 30' poles that were broken off. The only
thing holding them were the wires they were supporting. "I was much
younger then!" I wouldn't do it now even if I were able to climb. I
doubt those 20 to 30' poles were more than 5' into the ground.(Give or
take). Those poles were "OLD", dried out, and looked like a porcupine
from all the times they had been climbed. They were so dry, I'd bet one
man could have lifted and carried an entire pole by himself. Hugging a
pole had a terrifying meaning. More than once I had my pant legs pinned
to my legs! It still makes me sweat just thinking about it.
The pole at the end of a run is back guyed with a substantial anchor.
Even so, after ice storms, I've seen the end pole "BENT" with an almost
unbelievable bend. The line to our house in the country had a maximum
span. That pole was an excellent example of that bend with the power
line about 3' off the ground at mid span. Once the ice was off the pole
was nearly straight and the power line back where it belonged. HOWEVER
about a quarter mile West of me a pole gave out on a NS line and took
neatly a quarter mile down in both directions. There was nearly 3" of
ice on that line. The tips of the elements on my 5L 20 meter KLM
monobander were pointed nearly straight down. Considering KLM had those
elements tipped up, that amounted to more than 90 degrees total, but
when the ice dropped off they went back to normal.
OTOH My "finished" basement had nearly a foot of water in it. The power
came on just long enough to pump out the basement before it went out for
another week.
It was "clean" and very cold water, so when the power came back on and
the basement was pumped out, we set up a series of portable 4500 watt
heaters plus fans to dry out the basement. Other than squishy carpet for
a few days, it only ruined some paneling in one room.
After all that the point is, I doubt the power and telephone companies
pole planting procedures would be a good model for supporting Yagi
antennas at 30 or 40 feet. Still, I doubt they still do things the same
way as 50 to 60 years ago.
73
Roger (K8RI)
On 7/19/2015 12:57 PM, Kelly Taylor wrote:
I’m pretty sure the 20-foot utility poles in many neighborhoods are not 80 feet
long. (Three feet down for every one foot up would be 60 feet buried and 20 feet in
the air.)
I could see 20/3 (6.66 feet) as the required depth but not 3/20.
<whole lotta snipping>
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