The Arrow is an "open-sleeve" J-pole design. The other poles aren't
actively fed, but make up a critical part of the antenna design.

What are the pros and cons of an Arrow J-pole versus a Diamond X50A pole?

The Diamond X50A has a somewhat higher gain than the Arrow on 2 meters
(about 2 dB higher, if I'm reading the stats correctly) and a
significantly higher gain than the Arrow on 70 cm (about 5 dB higher).

The Arrow is about 6" shorter than the Diamond (might fit into an
attic space where the Diamond will not), has been tested at power
levels of up to a kilowatt (the Diamond is rated for 200 watts), and
costs only 40% as much as the Diamond.

The Diamond has decoupling radials, and I infer that it's less likely
to have a feedline-RF situation than the Arrow - its actual pattern
may be more consistently like its theoretically-calculated pattern.

The Diamond looks more like a traditional antenna... the Arrow is more
likely to get "What the bleep is that thing?" questions, if mounted
outdoors.

The Arrow may be easier to field-repair, since it's mostly just
aluminum angle and rod stock.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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