Hi Mike,
You wrote:
> The spacing will be .56 wavelengths apart.
> Here is the question.
> Is that close enough to .5 wavelengths to allow them to work properly?
Absolutely. Gain actually goes up as spacing is made wider, up to about .65
wl spacing. No change in phase is needed, assuming you are using the array
broadside (it will fire in the same directions as the lower frequency
dipole, but with a more narrow pattern).
You still use co-phased phasing, no matter what the spacing for a broadside
array. Broadside in-phase will give you a nice pattern on 30 with good gain
(zero degree phase shift), and broadside out-of-phase will fill all the
nulls and give you a clover pattern with less gain.
> The idea is to be able to switch between broadside and end fire, by
> switching in and out a 1/2 wavelength of coax.
I use a 180 degree transformers, and save coax. But that is on 160 meters,
you won't save a lot of cable on 30m. Should work just fine.
Lots of radials is better, either on the ground or in the air makes no
difference. 30 or so will get you over the "loss-hump". With a few radials,
you need to isolate the feeders with common mode chokes and elevate the
radials...and even then will suffer a performance shortfall of a few dB.
73 Tom
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