I'm testing a 2/2 40m stack that uses a Cushcraft 402CD@70' and a XM240@130'.
I'm feeding this with a WX0B stackmatch. The 402CD is directly coax fed with
some ferrite beads over the coax , and the XM240 uses the Cushcraft MNXM
balun.
I'm finding the 2 antennas seperately to be close (within 3-5 dB of each
other) as expected. What I find that bothers me is that the stack is almost
always slightly weaker than either of the antennas alone. I wonder if it is a
phasing problem?
If so, the bottom antenna would be easier to test phase as I can tell which
side of the driven element the center/ground of the coax are connected to. I
need to find out what the phasing is on the MNXM balun for the top antenna so
I can tell if the bottom is out-of-phase. Does anyone know how this balun is
wired?
Any ideas/suggestions would be appreciated.
73,
Will
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