Don Havlicek wrote:
>The 'right triangle' system utilizes two verticals per selected
>direction with the third 'floating'. The 'equilateral triangle' system
>uses all three verticals simultaneously,
Any triangle system can be used with either two or three elements
energized - check with ON4UN's book for details. In either case, the
most practical and versatile system for beam switching is the
equilateral triangle.
When only two elements at a time are used (the third being
disconnected), an equilateral triangle gives three directions along the
sides. With three identical elements and ground-planes, you have easy
reversal for a total of six directions.
When all three elements are used, usually one is driven with 100%
current, and the other two are driven at the same phase with about 50%
current each. The beam directions are off the top or the bottom of the
triangle (so they are moved around 60deg compared with the two-element
case). The gain is higher using all three elements, but beam switching
is much less simple so you may be practically restricted to only three
directions.
Any right-angled triangle would be less versatile than either of these
equilateral cases.
--
73 from Ian GM3SEK
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