The free-space Green\´s function of electromagnetics is transformed to a form which simplifies analyses of wire structures. The useful property of the new form is that it enables one to compute the electric field component

by applying only [

] to a potential integral (with new Green\´s function) even though such an integral is, in general, to be taken over currents that are not

-directed. It can be shown that the transformation effectively yields

in terms of a TM representation.