Interaction between dipole and beam
 

The QST article about the HyGain 40/30 meter rotatable dipole has my
interest. (It discussed using relays to change the dipole between 40 and 30
meters.)

My "small gun" station has a 3-el SteppIR on a 55-foor crankup/crankover
tower. The mast extends about 5 feet above the top of the tower. If I add
the rotatable dipole on the tower, should it be below or above the beam?
Will the spacing (about 4 feet) be so close that I degrade the beam? Would
a slightly longer mast be a major improvement? (I already have a dipole and
half-sloper wires connected near the top of the tower, sloping to about 10'
at the ends.)

With all the publications about ham antennas, it seems there is little
reference material about antenna interactions. I realize that each situation
is unique and it is a complex subject. Nevertheless, there seems to be very
little published in this area.

Bill
W2WO