[en] A power supply for the filament of the MEA klystrons is described. The supply is a 1 KW 625 Hz generator. Between the supply and the filament a high-voltage separation-transformator with rectifier is positioned. Since the filament has to be heated up gradually, the filament supply rules up in about 20 minutes. The finishing of the ruling up is signalized. Subsequently another 20 minutes has to be waited before the klystron is allowed to be put on high voltage. The output voltage of the supply is adjustable from about 200 to 400 volts. The supply is protected against short-circuiting and interruption of the output. This results in switching-off of the supply and in signalizing 'too low resistance' respectively too high resistance'. If by an internal disturbance the desired voltage and the output voltage deviate from each other, the supply drops down and indicates the error report over-voltage' or under-voltage'. The supply can be put on 'stand-by' or 'on' externally. Also external protections canb e connected to it, like: cooling, vaccuum etc.. When one of the protections drops down, the supply will drop down and give an error report. (author). 15 figs.; 1 tab