A high data rate coupler system comprising an isolation transformer comprising: a transformer core having a first surface and a second surface; a first through-bore extending through the transformer core from the first surface to the second surface, the first through-bore having an elongated profile with at least a portion of the elongated profile providing a first flat winding surface; a second through-bore extending through the transformer core from the first surface to the second surface, the second through-bore having an elongated profile with at least a portion of the elongated profile providing a second flat winding surface, the second flat winding surface spaced apart from the first flat winding surface by a central portion of the transformer core; and at least one multi-wire cable comprising a first conductive wire, a second conductive wire, a third conductive wire, a fourth conductive wire, a fifth conductive wire, and a sixth conductive wire, the second conductive wire positioned between the first conductive wire and the third conductive wire and the fifth conductive wire positioned between the fourth conductive wire and the sixth conductive wire, wherein: the first and third conductive wires form a first primary winding of the isolation transformer and the fourth and sixth conductive wires form a second primary winding of the isolation transformer, the first and second primary windings connected in series to form a center tapped primary winding: the second wire forms a first secondary winding of the isolation transformer, and the fifth wire forms a second secondary winding of the isolation transformer, the first and second secondary windings connected in series to form a center-tapped secondary winding; and wherein the high data rate coupler system further comprises a choke wound with respective end segments of the second conductive wire and the fifth conductive wire. a transformer core having a first surface and a second surface; a first through-bore extending through the transformer core from the first surface to the second surface, the first through-bore having an elongated profile with at least a portion of the elongated profile providing a first flat winding surface; a second through-bore extending through the transformer core from the first surface to the second surface, the second through-bore having an elongated profile with at least a portion of the elongated profile providing a second flat winding surface, the second flat winding surface spaced apart from the first flat winding surface by a central portion of the transformer core; and at least one multi-wire cable comprising a first conductive wire, a second conductive wire, a third conductive wire, a fourth conductive wire, a fifth conductive wire, and a sixth conductive wire, the second conductive wire positioned between the first conductive wire and the third conductive wire and the fifth conductive wire positioned between the fourth conductive wire and the sixth conductive wire, wherein: the first and third conductive wires form a first primary winding of the isolation transformer and the fourth and sixth conductive wires form a second primary winding of the isolation transformer, the first and second primary windings connected in series to form a center tapped primary winding: the second wire forms a first secondary winding of the isolation transformer, and the fifth wire forms a second secondary winding of the isolation transformer, the first and second secondary windings connected in series to form a center-tapped secondary winding; and wherein the high data rate coupler system further comprises a choke wound with respective end segments of the second conductive wire and the fifth conductive wire. the first and third conductive wires form a first primary winding of the isolation transformer and the fourth and sixth conductive wires form a second primary winding of the isolation transformer, the first and second primary windings connected in series to form a center tapped primary winding: the second wire forms a first secondary winding of the isolation transformer, and the fifth wire forms a second secondary winding of the isolation transformer, the first and second secondary windings connected in series to form a center-tapped secondary winding; and wherein the high data rate coupler system further comprises a choke wound with respective end segments of the second conductive wire and the fifth conductive wire.