Abstract: The method of controlling and/or monitoring an optical transmission of message signals over an optical line in a repeater station includes providing a device (45) for generating further optical secondary signals from the received optical secondary signals without generating a stable optical carrier signal for the secondary signals in the device (45). This device (45) includes a hybrid circuit (451) for splitting the received optical secondary signals to form a first branched optical signal portion and a second branched optical signal portion, an optical monitoring and/or control receiver (454) for generating control and/or monitoring signals (456) from the first branched optical signal portion and an optical modulating device (458) controllable by the control and/or monitoring signals.

Abstract: The device for coupling and decoupling signals of two transmission channels has an optical amplifier and a first optical coupler connected upstream in a transmission direction from the amplifier and a second optical coupler connected downstream from the amplifier. The first coupler (K1) decouples signals of a first transmission channel fed to the amplifier. The second coupler (K2) couples signals of another transmission channel (m) (n) together with signals in a second transmission channel (o) into it from the amplifier. The device is suitable as an add/drop multiplexer and couples and decouples transmission channels using only one optical amplifier for each transmission direction.