> Can 2 seperate beverages (seperate feedlines, seperate
> transformers, seperate ground rods) share the same
> supports? I have a 585' NE beverage I recently put up
> that uses 5' steel conduit supports with PVC pipe
> insulators at the top (~ 7' height). I have cut slits at
> the top of the PVC pipes and run the wire through those.
>
> Could I drill a hole in the PVCs about a foot vertical
> down from the current wire and run another wire through
> these as an independent SW beverage without excessive
> coupling of the antennas?
Alan,
You can get away with a dozen feet or less when two wires
are parallel for large portions of the wavelength, but not a
dozen inches! Cross coupling between the two antennas
will be severe when two conductors are only spaced one foot
over a distance of 585 feet! What you will have, in essence,
is a single wire terminated at each end with a feedline
across the termination.
Since that is what you will have, you might as well clean
the system up. Either install a two wire reversible Beverage
or use a single wire with a feed transformer at each end,
and terminate the unwanted direction at the antenna switch
with a resistor that matches the line.
Many of my Beverages have a good transformer (like the DX
Engineering BFS-1) at each end. 75 ohm lines go to a
switching box that terminates the unused direction in a 75
ohm resistor.
73, Tom
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