A Balance-Unbalance Transformer for Induction Noise Reduction in Cables

A balance-unbalance transformer has been used in transmission systems to reduce induction noise, which is translated to in-phase longitudinal current along a twin cable toward the g r o u n d . E q u i v a l e n t longitu­ dinal current circuits for the transformer have been derived, and computation formulas have been obtained. Two transformer configurations which eliminate the need for any shield between the windings are newly intro­ duced, and good agreement between experimental data and calculated data is demonstrated.