| 摘要 |
1499961 Automatic exchange systems INTERNATIONAL STANDARD ELECTRIC CORP 8 Jan 1976 [16 Jan 1975] 00626/76 Heading H4K A path through an electronic switching network EKF, constituted by switches having resistances Ra1-Ran, Rb1-Rbn is coupled to a line transformer UET and a junctor transformer UEV via an arrangement of Zener diodes Z1-Z6 and impedances R1, R2 substantially as shown, and a damping reduction device NIC is provided with a negative impedance such that the total series impedance across the switches, the impedances R1, R2 and the clamping reduction device is zero. The impedances R1, R2 may be resistors or inductors having air-core coils. The purpose of the Zener diodes is to protect the switches against over voltages. |
