On 30 sep, 03:39, Anonymous wrote:
Of all the HF antennas one might reasonably make out of wire or
aluminum tubing, which produces the strongest groundwave?
Ground-mounted quarter-wave vertical? Horizontal dipole at a height of
1/4 wavelength? Or what? I'm sure someone must have experimented, or
done computer modelling, to seek an answer to this question but I am
not finding any information.

--
-30-

Hello "Anonymus".

I assume that you want to maximize field strength close to ground.
At the low HF (and of course medium wave), the surface wave
contributes lots to the signal strength. These ones you can only
excite with a vertical polarized antenna. Also elevated vertical
antennas induce surface waves, so a ground connection is not mandatory
(but many times required practically because of antenna size).

As mentioned by other poster, 5/8lambda vertical fed over a good
ground network gives highest gain in horizontal plane (with a minor
side lobe).

At high frequency (and low ground conductivity), surface waves do not
play an important role. In that case height is the determining factor
(with high directivity in the horizontal plane). Polarization is of
less importance.

Best regards,

Wim
PA3DJS