In a message dated 98-08-20 11:41:42 EDT, ni6w@yagistress.minden.nv.us writes:
<< Hi,Sigh, this can be difficult to explain!Ok , Both of the oval and
rectangular
values in the Rohn drawings are projected
area.
The Oval one is larger, because the round members have less drag, hence, less
load, hence, lower "effective area". The larger oval value generates the same
applied load on the tower as the rectangular one.
If the antenna is made with round tubing, use the oval area. If it is made
from
box tubing, use the rectangular area.
Is that any better? >>
Yes, I understand that.
So the newly revised Hy-Gain figures are for ROUND MEMBER PROJECTED
AREAS? And while the antenna figures changed (increased), their application to
RMPA comparisons did not change? Aren't all ham antennas (approximately)
calculated for round members? What method do you use in YagiStress?
Cheers, Steve K7LXC
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