The usual formula for computing the distance to the far-field of an antenna is 2 D^2 / lambda, but I've seen several references to occasions when this does not apply.
I'm looking at trying to match a folded dipole (Zo = 4 * 73 Ohms = 292 Ohms) using a 4:1 balun consisting of a length of coax which is electrical a half wave. The balun should give me an unbalanced si ...