"-.-. --.-" wrote in message
...

"Richard Clark" ha scritto nel messaggio
...

Consider: a commercial AM quarterwave, vertical antenna is probably
95% to 99% efficient. To have an incredible efficiency would add only
4% more to a very simple design that has been around for 100 years.

+0.2dB or less is not incredible efficiency.

You cannot hear 0.2dB difference in sound, you cannot measure 0.2dB RF
difference except with great difficulty.

73's
Richard Clark, KB7QHC

Thanks for reply, Richard.
Take also into account that, although i don't know much mathematic, i
don't
have any doubt that is impossible that this kind of antenna can have a
great
or also medium efficiency.

Considering your 1/4 wave AM broadcast antenna example, is not an accident
that nor military nor broadcast installations used in the past a type of
antenna like the EH/HZ...
... and military brains have knowledges that we in the "civilian" world
can
use maybe after 20-30 years.



.... if the first 'nor' should be interpreted as 'neither' then I'd agree.
In the UK, 5/8 wavelength vertical radiators have been popular for AM radio
broadcasting, singly (e.g. used for some BBC services) and in arrays (for
commercial radio, eg. Saffron Green, north London) usually with _very_
extensive earth mats. The Isle of Man International Broadcasting company
made a big deal about ten years ago about their intention to use a CFA for
broadcasting on 279 kHz, initially from the island, and latterly from a
modified oil rig in IOM water (e.g.
http://www2.hard-core-dx.com/archive...msg01127.html). However, this
still isn't on the air so one may speculate.

Chris