For me at least, this remains in my mind as
an "unsolved antenna mystery". A few have
asked "why bother messing around with the
forked radials idea - just put down 60 1/4 wl
radials and get it over with?"
In my case, I'm considering forked radials (at
least, a minimal amount of wire and "stuff to
duck under when mowing the lawn) for a Butternut
vertical on a mast mount (at ~10' to 20' height)
with the radials sloping to ground. 60 .25wl
radials sloping to ground at ~30 degrees from a
height of 15' turns a simple secondary antenna
into a rather complex one. Assuming that
because it is mast mounted and off the ground
(the radials are somewhat elevated to begin
with), perhaps a greatly reduced number of radials
eminating from the mast would suffice.
I'd like to eventually model this, but the only
modeling package that I have at the moment is
the FREE one - MMANA (a fun free modeler - check
out http://www.qsl.net/mmhamsoft/mmana/) which
probably isn't ideal for this sort of thing.
Once I get around to it, I'd like to model
"standard forking"...
where A=B=C=D=(~.125 wl) and A slopes to ground
from 10' at the mast (M) at ~40 degrees.
/
B /
/
A / C
M-----------------
\
\
D \
\
"multiband forking"...
where A=.125 wl on say 40m and ~.06 wl on 80m,
B=.19wl on 80m (to finish the 1/4 wl), C=.125wl
on 40m, etc.
"upclose forking"...
where A is very close to the mast (a 45 degree
slope) and forks as soon as A hits the ground.
and finally "reverse forking"...
I doubt this makes any sense at all.
^
A/ \
/ \
C / D \
-----<------->M
\ /
\ /
\ /B
V
In fact, I have my doubts about quite a bit of
this (especially the multiband forking - which
electrically needs a lot of work), but it should
give me something to do while waiting for the
ground to thaw to actually try this stuff.
Pat, N0HR
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