Topband: phasing line lengths for phased verticals

[Tom W8JI]

I really DO have 80m verticals that are 1/2 wave apart. (incidentally I 
share the radial fields with the 160m antennas which are 1/4 wave apart)

So the question remains, how to properly feed phased verticals that are 
physically 1/2 wave apart>>>>

If It was my array, I'd add an element in the middle hanging from a catenary 
rope.

One problem with 1/2 wave spacing is the distance is too wide for effective 
end-fire (out-of-phase) gain, and not quite wide enough for best broadside 
(in phase) gain.  More important, you cannot obtain a unidirectional 
pattern.

You might consider adding a third parasitic element midway. With a minimum 
of hardware, this would give you a simple reversable 80 M unidirectional 
pattern in the same directions as the 160 elements. You could also still 
have broadside bidirectional and endfire bidirectional, so you would have 
two unidirectional patterns and two bi directional patterns with no more 
than a inverting transformer and a switch.

Of course SWR would be a slight issue, but tolerable with some planning. 
Mutual coupling would cause impedances to change with directions.

Otherwise, all it takes is an inverting transformer and a relay to flip 
between bidirectional patterns.

73 Tom