| 摘要 |
A transmission bridge comprising, arranged between two line terminals (1, 2) a series arrangement of two primary windings (3, 4) of a transformer and an intervening capacitor (20), two supply resistors (6, 7) each connected to a respective one of the terminals and to power supply (10, 11), secondary windings (13,14) of the transformer being used to provide voltages equal to the a.c. voltages appearing at the terminal and these voltages are fed via respective alternating current circuits (8, 9) having a high input impedance, a low output impedance and a gain factor equal to unity, the outputs (17, 19) of these circuits being connected to the respective supply resistors in such a manner that the same a.c. voltage appears at both ends of each resistor. As a result, wanted anti-phase voltage signals between the terminals are not attenuated by the supply resistors whereas the supply resistors do attenuate unwanted in-phase signals. <IMAGE> |
