Abstract: In a method for determining a power of an amplified spontaneous emission in an optical fiber amplifier for a WDM signal, wherein the optical fiber amplifier includes at least a first amplifier stage having a predetermined output power set for a measured input power, a first mean inversion is determined for the first amplifier stage. A first output power of the amplified spontaneous emission is determined at an output of the first amplifier stage by reference to tabulated values which depend on the first mean inversion.

Abstract: The invention concerns a thyristor column with disc thyristors which are stacked on top of each other and are mounted resiliently. A heat sink, which serves simultaneously as a conductor of electric current, is interposed on each side of each disc thyristor. Between the heat sinks of succeeding disc thyristors, a spacer element is inserted, on which ferrite cores are lined up. In this embodiment, the transient current is limited by the choke formed by the spacer element and the ferrite cores. The resistors of the external R-C components can therefore be designed for less power.