The legal limit is defined in terms of EIRP,
1 to 5 watts. You only need a few percent
efficiency if you have a reasonably powerful
transmitter. Any decent 160 meter transmit
antenna, with additional base loading, will
be fine. Transmit arrays of course don't make
sense.
BTW, the wavelength is 630 meters.
Rick N6RK
On 2/13/2012 6:48 AM, Rik van Riel wrote:
> Things are looking good at WRC-12. Approval of an international
> amateur radio allocation around 470 kHz seems very likely:
>
> http://www.arrl.org/news/agenda-item-1-23-passes-committee-moves-to-plenary
>
> This does, of course, lead to the question of antennas.
>
> What can people without a few acres to dedicate to 600m do to
> get a vaguely decent antenna?
>
> I started modeling an inverted L with an FCP and a loading
> coil the size of a rain barrel. Then I added more top wires,
> in more directions, and the loading coil is only half the size
> of a rain barrel :)
>
> Before loading coil losses, gain is about -10dBi!
>
> Nowhere near as easy as 160m, but this could be a very
> interesting antenna challenge for hams...
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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