Feeding the Double X

There are three basic feeding patterns for the Double X.

For an end fire pattern, the elements are fed across the ridge line.

For a broadside type pattern, the elements are grouped differently, and fed this way

 

And finally, you can also feed them so you get a 45 degree angle

Obviously, one can mirror or reverse the above schemes to get the rest of the 8 cardinal directions.

How much phase shift?

The phase center of the sloped inverted V is somewhat indeterminate, so doing a phasing calculation based on isotropic point source radiators isn't particularly useful. Instead, a series of simulations were run using NEC2 with current sources on each element and adjusting the phasing.

antenna/dblxfeed.htm - 14 October 2002 - Jim Lux