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inter bay cables

 
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inter bay cables
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stylzmovement
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does anyone knows the formular for getting the lenght for the inter bay cables for a 2 bay or a 4 bays antenna system?
Sun Feb 11, 2007 4:52 pm View user's profile Send private message
intertech
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Spacing of multiple bays:
Spacing between bays (Wavelength) in inches = 11803 divided by the Frequency in MHz.

INTERBAY FEED LINES.
They must all be the same length for proper phasing and power distribution of the antenna, if your spacing is 1/2 wave or full wave your cable should match, see formula above. If you wish to introduce a downward tilt pattern or phase delay I can send you the interbay cable spacing formula.

There are unique variations to the feed systems of antennas that have bay separations other than one wavelength. Uniform, in phase operation (RF excitation, not spacing) of the antenna's bays is requisite in any broadside array. In order to achieve this, several variations upon the standard feed schemes can be used.

In the case of one-half wavelength separations, a sub-feeder system can be used or the elements can be shunted directly across the main feedline at half-wavelength intervals by inverting every other bay. The latter method corrects the phase inversion inherent at every other feedline tap point by reversing the side of the dipole receiving the RF excitation; effectively restoring the bay spacing to in-phase operation.

However suggest you keep your radiators at a full wave spacing which keeps it simple to follow, keep in mind the radiator at the top of your array is numberd 1.

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Mon Feb 12, 2007 6:11 am View user's profile Send private message Visit poster's website
stylzmovement
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so for example if my antennas are spaced at .75 of a wavelenght, what wavelenght should i cur the cables to 1 wave
.75 wave
0r 1/2 wave
Mon Feb 12, 2007 5:16 pm View user's profile Send private message
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