Will AA4NC wrote:
> I'm testing a 2/2 40m stack that uses a Cushcraft 402CD@70'...
> 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?
That definately sounds like the problem, based on my recent
experience. I had the exact same symptoms. Stack always worse
than any single antenna, sometimes dramatically so.
> Any ideas/suggestions would be appreciated.
Just swap the phase of the feeders on the bottom yagi and run some
more tests. It made a huge difference on my stack. You might want
to make the feedpoints identical, instead of one with and one without
a balun.
-Kirk K4RO
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