[TowerTalk] 4-Square Owners, etc, and Horizontal vs. Vertical

[T A RUSSELL]

N4KG  response below -

On Fri, 8 May 1998 09:13:52 -0400 "Dick Green" <dick.green@valley.net>
writes:
>> I suspect that verticals just don't work well when frequency is
>raised much above 80 meters. Anyone else have any thoughts on that??
>
>I think there's some truth to this, but I don't know why. I do know that
>I've never gotten a ground-mounted vertical to play on 10M worth a darn.
>I've had multiband verticals that worked OK on 15M and 20M, but they 
>were clearly inferior to a dipole. However, I've always had good luck
with
>ground-mounted verticals on 40M, both multiband verticals and 
>full-size (the latter are *much* better.) I think they are superior to a
high dipole 
>for long haul DX, and that's probably due to the lower radiation angle. 
>For closer communications, it's either a toss up or the dipole wins.
>
>As I recall, a ground-mounted vertical with a reasonable number of 
>radials (say, 60) is -3 dB down from a dipole. A dipole should be
superior in 
>the favored directions, but the radiation angle tends to favor the 
>vertical for DX. I believe a 4-square is about 5-6 dB up from a
monopole, so it 
>should be about 3 dB better than a dipole. That, combined with the lower

>radiation angle, should make the 4-square quite superior to a high
dipole. Most
>4-square owners I've talked to think so. It doesn't make a lot of 
>sense to me that your 40M 4-square didn't work well.
>
>73, Dick, WC1M

The answer to why verticals perform poorly on the high bands lies in the
pseudo-Brewster angle effect where low angles are sucked out unless
there is EXTREMELY good ground conductivity in the antenna foreground,
presumably for more than a wavelength.   This is why verticals DO work
well on the beach (remember 6Y4A?).

Below about 10 to 15 degrees, there is considerable low angle loss over
average earth on the higher bands.   The lower you go in frequency, the
higher the useful angles and the more difficult it it to install
effective 
horizontal antennas.

I recently added another tall tower (140 ft), allowing me to install a
full
size horizontal dipole broadside to Europe on 80M and an inverted vee
to JA / S.A.  This antenna is clearly better than both my elevated GP and
full size vertical in the woods with 30 radials, 3/4 of which are 100 ft
long.

The high horizontal dipole is usually better to south, central, and
western
Europe.  Very often, the vertical or GP antennas are 6 to 10 dB better to
Scandanavia.  The high inverted vee is always better to South America,
the Antarctic region, VK0HI before sunset, and SE Asia in the mornings.
The inverted vee enabled me to work BV, BY, V85, 9M6, and 9M0C on
the very long and difficult short path  (lots of ground reflection loss)
over 
USA, VE, KL7, UA0, BY to reach those distant places this past winter.

de  Tom  N4KG


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