Topband: Beverages sharing supports?

[Tom Rauch]

> 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