<< Some good information about how to set up a balloon
supported antenna system. The two balloon full wave antenna
looks like an effective system - but more complicated to deploy
than a 1/4 wave single balloon vertical. This may be a gain
antenna for DXpeditions to consider for 160M. - N0JK >>
Besides being more complicated (had my experiences with wrestling baloons!)
article in CQ magazine by K9ES and AD4ES states that full wave antenna has abt
4.5 dB gain over quarter wave. What is neglected is the factor when that
antenna is bent into L shape, the radiation pattern gets changed, horizontal
component comes to play, becomes antenna and radiation pattern and gain
"figures" are not what fullwave vertical would exhibit. (Where are the
computer calculated radiation diagrams?)
Back to old song about using verticals: one has to consider radiation
pattern of antenna. When we get over abt half wave with vertical, lobes get
close to the ground, more dependent on the good ground system (for low
angles). Majority of propagation on 160 is at around 30 - 45 deg angles. (This
is why quarter wave verticals play best - widest vertical angle coverage)
Appears that the best configuration to get some gain is to use broadside
phased quarter wave verticals, or bobtail configuration: 1/4 up, 1/2
horizontally, 1/4 down, and use radials (few elevated or lotsa burried) under
vertical wires.
Another claim in the article about "The second advantage was the absence
of a radial system" - well, this was rehashed here before. Proximity of the
ocean helps quite a bit, but piece of wire going into the ocean would give
much more than 8 ft ground rod in the sand.
As for my experience with balloons? Its fun, they work, but for
contesting I would only use it as another (spare, second) antenna. Too much on
the mercy of winds and weather. Can't count on it being up. Kitoons might be
better, but still under Murphy's control.
Back to loaded verticals and phasing shpagetti.
73 Yuri, K3BU, VE3BMV
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