Abstract: A wideband balun for converting between unbalanced and balanced signals and impedances utilizes two single-ended networks connected in parallel at the unbalanced side. The networks provide equal power split and equal phase slopes with midband phase shifts of +90 and -90 degrees in order to give equal-amplitude, anti-phase balanced outputs over an octave or more bandwidth. Printed circuits construction including a folded microstrip line provides an effective implementation at UHF frequencies.