Hi Jerry, I am running a stack consisting of a Cushcraft x520 at 150 ft
and a c31xr at 100 ft and a klm kt34 at 50 ft. I was able to get the
phasing right by using a mobile rig parked about a 1000 ft away to
transmit a signal and checked the signal in the shack using a dual trace
scope to determine the phase angle of the different antennas and used
extra feed line to get the phasing right. You have to calculate the
difference in distance of the top, mid and bottom antennas and add that
to the phase relationship calculations. I did this for 20m only but the
same procedure is used for the other bands. I would recommend you put a
c31xr or similar antenna up at the 40 ft level and run equal lengths of
the same coax from the two antennas into the shack and check the phasing
on all bands and use one of Jay's boxes to phase them. Some people have
reported good results using a continuously variable phase box a la ARRL
antenna compendium #3 which gives you more flexibility in controlling
the take off angle.
gl es 73 Steve
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