I had used 3/4 wave spacing for a pair of CushCraft 7 element 2m beams.
Rotor was a U100, but the lower beam was only a few inches above the rotor.
Assuming the antennas are about 50 Ohms impedance, you phase them by running
equal lengths of 75 Ohm coax from each antenna to a T connector. The lengths
of the 75 Ohm coaxes must be an ODD electrical multiple of 1/4 wavelength,
as for instance 3/4 wavelength. As I recall, the calculated stacking gain
for my setup was about 2 db.

Tam/WB2TT
"news.verizon.net" wrote in message
...


After over 40 years in ham radio I have decided to try my hand at VHF +
weak
signal modes. Unfortunately, due to a severely restricted budget and
physical space for antennas, I am trying to put together a small VHF +
station that will provide some fun.

Following a 1999 QST article I have converted two Radio Shack 6 element FM
yagis to 5 element 2 Meter beams. I need to stack these and I am wondering
what the proper procedure and spacing is for this array. The old VHF
handbook says 5/8 wave length if they booms are under 1 wavelength. The
ARRL
HB (2003) says for booms 1 wavelength long use a 1 wavelength spacing.
Unfortunately, I cannot space them at 1 wavelength. The rotor I am going
to
use won't support that spacing. Can anyone point me in the right direction
on stacking and phasing these two beams?

73 Rich WB3WVC