X-ray diagnostics generator having a rotating-anode X-ray tube

摘要

The invention relates to a circuit arrangement by means of which the frequency of the AC voltage of the motor (3) can be measured and can be compared with a predetermined value. A pulse sequence which corresponds to this frequency is supplied to a programmable decrementing counter (13) which is set by each pulse to a value corresponding to a predetermined frequency and is connected to a pulse generator (15) whose frequency is high in comparison with the frequency to be measured, and as a result of whose output pulses it is decremented (it counts backwards). The decrementing counter (13) has an output (16) at which it supplies a pulse when it reaches zero and which is connected to the reset input of a counter (17) which is incremented by the pulse sequence to be measured and supplies an output signal if it has not been set to zero between a specific number of input pulses. <IMAGE>