Abstract: A modem coupling circuit comprising: (a) a transformer 1 having a core 1a including a gap formed therein, primary windings N1a, N1b constituting a bifilar wound coil which is wound around the core 1a, forming a single layer and connected to power lines L1, L2, and a secondary winding N2 connected to a transmitting circuit 2 and a secondary winding N3 connected to a receiving circuit 3, the secondary windings N2, N3 holding the single layer of the primary windings between; (b) a coupling capacitor C1 connected to a middle point between first ends of the primary windings, the first ends being not connected to the power lines L1, L2; (c) current limiting resistances R1a, R1b connected to the primary windings N1a, N1b having a bifilar construction; (d) drive resistances R2a, R2b connected to the secondary winding for transmission N2; and (e) terminating resistances R3a, R3b connected to the secondary winding for reception N3.

Abstract: A modem coupling circuit comprising: (a) a transformer 1 having a core 1a including a gap formed therein, primary windings N1a, N1b constituting a bifilar wound coil which is wound around the core 1a, forming a single layer and connected to power lines L1, L2, and a secondary winding N2 connected to a transmitting circuit 2 and a secondary winding N3 connected to a receiving circuit 3, the secondary windings N2, N3 holding the single layer of the primary windings between; (b) a coupling capacitor C1 connected to a middle point between first ends of the primary windings, the first ends being not connected to the power lines L1, L2; (c) current limiting resistances R1a, R1b connected to the primary windings N1a, N1b having a bifilar construction; (d) drive resistances R2a, R2b connected to the secondary winding for transmission N2; and (e) terminating resistances R3a, R3b connected to the secondary winding for reception N3.

Abstract: A noise absorbing device is adapted to prevent radiation noise or induction noise from a cable connected to an electronic apparatus. A pair of holder segments (11 and 12) receive core pieces (20) in receiving recesses and are coupled by hinge portions (19) so as to be brought into butt contact with each other so that the pair of core pieces (20) form a cylindrical body with a cable extending therethrough. Elastic pieces (31) are interposed between the pair of core pieces (20) and the pair of holder segments (11 and 12) in order to provide an elastic force to the core pieces (20) so that the core pieces are slightly protruded from opening edges of the holder segments (11 and 12). When the pair of holder segments (11 and 12) are brought into butt contact with each other, the pair of core pieces (20) are put into press contact with each other by the elastic force of the elastic pieces (60).