In a message dated 3/11/2005 8:31:04 AM Eastern Standard Time,
i4jmy.mauri@gmail.com writes:
>>Just to give a couple of practical "european" examples, although US
west coast is generally a matter of very low angles on 10m, east coast
it's not, expecially with a wide open propagation.
An antenna system which is excellent at 3° but unable to manage angles
in the range of 6-9 degrees is a good insurance of bad results.
On 20m, an antenna at 200ft from ground is often a gap beeing unable
to hear at critical elevations.<<
In a nutshell: you need to be able to adjust your antenna performance,
pattern to prevailing propagation. More, different antennas, stacks, verticals
will
do wonders at different times.
Now that we are heading to low sunspots, the stacks, high horizontal antennas
and vertical arrays will dominate the bands. During sunspot maxima, any piece
of wire half way up will get you out.
To underscore Mauri's example, I saw dramatic demonstration in 10m contest
from my OK friends:
OK1RI had i believe fixed, non-switchable 4 stack of long Yagis
OK2RZ had three different antennas at various hights, but none producing low
angle like OK1RI stack.
At the beginning of the band opening OK1RI was S9, head and shoulders above
rest of Eu.
OK2RZ was barely above the noise, S3.
Couple hours later into the opening, unbelievable - OK2RZ was S9 + 20, OK1RI
S6.
OK1RI was probably punching holes in W6 by then, but missing lot of little
pistols with their "grounded" antennas.
For DXer, generally the higher, the better, they mostly chase that rare, far
away one.
For contester the name of the game is max QSO and multipliers in allotted
time and that means arsenal of variety of antennas capable of changing pattern
and angles. Those who tried stacks and variety of antennas can testify to it,
and they feel crippled when operating one "miracle" antenna in the contest.
Does size matter? It does, when properly designed, optimized. (You could have
Wilson 5 el. monobander not beating TH6) Generally bigger size implies more
gain, louder signal, more RX sensitivity and noise discrimination. If you can't
hear'em, you can't work'em. If antenna doesn't deliver signal, there is no RX
in the world that would decipher it. I realized and learned that from Jim
Lawson, W2PV, who took great care in designing the antenna system for his
situation and creamed competition. That got me going on the quest for max gain
antenna on a boom and produced my Razor designs (Quad-Yagi combo). What matters
more
is the flexibility to control the angles to fit prevailing propagation and
desired target areas. Stacks, polarization diversity, salt water can do
"miracles". Can pair of verticals cream stacks? They did, see 6Y2A vs. PJ9A M/M.
Now if you setup 16 vertical array on the beach......
Antenna system is the most important part of the contest station. Succesfull
contesters probably spend about 70% of money on antennas and rest on rest. Now
finding good RF location to maximize the scores in particular contest is
another story - beaches in Africa and S America rule for CQ WW.
Yuri, K3BU, VE3BMV, VE1BY, C6AYB
Tesla RC N2EE, NT1E, VA1A, VC1A
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