Jim,

I don't know where you get this from. I just ran EZNEC on a 10 m vertical
dipole with the following results:

A) Bottom at 8 feet, gain at 5 degrees is -2.44 dbi.

B) Bottom at 42 feet, gain at 5 degrees is +2.75 dbi.

If you want to work locals, the greater height will also help to get clear
local obstructions, like small hills

Tam/WB2TT
"Jim Leder" wrote in message
...
But, don't get it up to high. EZNEC shows that when the bottom end is a
half
wave length above ground, the TOA goes up over 40 with not much
improvement
in gain. The vertical half wave dipole seems to be at it's best a quarter
wave above ground (meaning the bottom end is only 8 feet up on 10). So,
the
top insulator should be up about 24-25 feet. When installed at this
height,
the TOA is below 20 and the gain is almost the same as the higher version,
roughly 1.4dbi. The antenna does not require radials.


"Keyboard In The Wilderness" wrote in message
news:PCzLb.55730$m83.35174@fed1read01...
the vertical dipole and radials

Just picture a 1/2 dipole horizontally -- then rotate it 90 degrees (or
stand it on end) -- same antenna -- different polarization.

So this picture should clarify why "No Radials".

The lower end is the other half of the dipole - it radiates in
conjunction
with the upper half.

Others have advised you about the radiation from "Radials"

--
73 From The Wilderness Keyboard