wrote in message
oups.com...
A 150 foot boom ( say 20
elements for example) beam might be perfect for picking up t he lower
angle, which is what I thought you were looking for. The t hree
element beam will bring in higher angle signals as the lobe will
have
a higher angle. A dipole will likely have even a higher, po ssibly a
NVIS angle. ...................................
Dunno...I've never compared super long yagi's vs short ones, but I
don't
think boom length has a drastic effect on the takeoff angle...
Mark I never used the word "drastic" however the long boom antenna
will lower the TOA by around a degree. The reader has to determine
the value of this for himself. If one reviews the incomming signals in the
ARRL literature one can see the percentage of signals that come in from
Europe
at 9 thru 13 degrees.These angles by the way are not to be confused with TOA
and explains exactly why a silly db can mean a lot.
It also shows that the long boom aproach has its limits with respect to
lower
TOA and height certainly changes the TOA more in terms of less complexity.
What I am looking for is the latter method but with less emphasis on feed
point height
which will require a deflection method to achieve lower angles. I am sure
that multiple reflectors
and a single director can be manipulated to do this
Regards
Art
The
height above
ground is what really determines that...Same for a dipole...A dipole
has a very
low takeoff angle *if* it's high enough..The various yagi's takeoff
angles *should*
be about the same as a dipole at that same height...Or seems to me,
without
looking into it farther. MK
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