> In a message dated 06-17-97 JEFF EDMONSON wrote to LARRY KUNZ:
> JE> A DB-224 has 4 elements, and as I remember they are all fed
> JE> simultaneously, meaning that the Z would be somewhere around 12.5
> JE> ohms, per.
> Jeff & Larry-
> Antennas like the DB -224 are typically driven through a
> phasing harness,
> that combines the individual dipoles' 50 Ohm impedance to match
> a 50 Ohm
> transmission line.
That, we knew ;-)
> It could get messy to combine an 8-dipole array using this technique.
> Does anyone know how the "big boys" do it with 8?
I'm also interested how they do it with 16 bays!
> My only thought is that they use folded dipoles
> that combine in parallel to have a 50 Ohm impedance.
> If so, the 4-dipole harness would work for 8-folded dipoles.
Double that, Fred, and let us know how that's done...
But, it would stand to reason that if the same harness would work for
4-dipole arrays, would work for 8, then doubling that again, would mean it
shouldn't have a problem working with 16 bays. however, it would be quite
space inefficient for anything under 440MHz.
73 = Best Regards
-Jeff KA5THB
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