[BC] Arrays On-the-Cheap - Was: Two-tower array designed for 990 running on 1030

[PeterH5322@aol.com]

>While short spacings may appear to have the benefit of a slight gain
>over a non-D counterpart, the downsides are high RSS:RMS ratio,
>poor bandwidth and low drive point impedances. The vectors in the
>main lobe do not add up to the total i.e. there is a residual.

Two stations in my area are operating with, or have proposed short-spaced 
arrays.

The first is three towers, 10/5 kW Class B.

The second is four towers, 50/50 kW Class B.

Both are asymmetric designs with unequal spacings. One is as short as 55 
degrees.

A benefit is a relatively broad, very deep null towards the Class A, 
off-axis, with a very broad minimum, also off-axis, towards a distant 
co-channel Class B in the first case, and towards a local first-adjacent 
in the second case.

Yes, the RSS:RMS ratio does stink in these cases.

I'm sure all other considerations aside, the goal was maximum power at 
minimum cost, while fitting within a fixed site.

The sites were existing, and were not originally intended for the 
ultimate use (both cases), or even for the same frequency (the second 
case).