On 11/28/2015 6:23 AM, Carl Braun wrote:
Any suggestions or websites available on ½ wl spacing and ½ wl radiators?
Carl AG6X
I did some modeling of this a long time ago. Basically, the
issue is that if you feed the 1/2 wave verticals at the base,
you need to have a *voltage* forcing feed, rather than the
usual current forcing feed used for 1/4 wave verticals.
This is tough to do if you need a 90 degree phase shift as
in a 4 square. However, you are in luck because you only
need a 0 degree or 180 degree phase shift. As long as
your array is physically symmetrical, any symmetrical feed
network will give the right phasing. I suggest a simple
T junction (in coax) with 1/2 wave lines to the verticals.
Make one of them 3/2 wave for 180 degree phasing.
The impedance at this point may be too high for an off
the shelf transmatch, so you might have to roll your own.
Rick N6RK
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