Jim Lawson, W2PV, solved the TOA problem on 20 M with a l o n g yagi at
~150' to open the band and his either/or/both stack(top antenna at about
70-80', as I remember) for normal band condition. Oh yes, Alpha 77s on most
bands, too!
Phil, KB2HQ, former neighbor of W2PV
" wrote in message
news:ODzKd.33178$IV5.6955@attbi_s54...
You can move the antenna boom up or down some 10 degrees and you would not
be able to tell the difference per
Lawson W2PV
Art
"Buck" wrote in message
...
On 28 Jan 2005 12:48:52 -0800, "art" wrote:
Most people have added an amplifier only to find out that the
difference in signal
was very small. Thus many people deride the value of a 'silly' db gain
whereas DX'ers say that a single db extra is a lot !
Fact is that most long distance signals on 20 metres come in at angles
of 11 degrees or less where as the 'normal' antenna has a TOA of around
14 degrees.
So where a dxer points to the extra 1db gain as being everything in
fact it is the lowering of the TOA that comes with the extra gain. In
my opinion if one designs his antenna for a lower TOA say 10 to 11
degrees then even tho its gain may well be below the dxers choise( a
very long boom or stacked antennas) the lower TOA with less gain will
show little difference
to the antenna of choics because the lower edge of the radiation lobe
will follow the same line and any extra gain provided will have the
same effect of adding an amplifier which is minimal compared to the
ability of capturing signals that arrive at low angles.
I believe it is time for antenna designers to concentrate less on
obtaining gain and instead concentrate more on lowering the TOA.
without the need of excessive real estate requirements.
What say ?
Art
I have always thought that if one changed the azimuth angle of a beam
it would improve a number of contact signals, pending the angle they
are reflected from the atmosphere.
--
Buck
N4PGW
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