Abstract: A damping circuit is described for the antenna resonance circuit (28) of a radio transmitter-receiver (10) which in a transmitting phase transmits a time-limited high-energy interrogation pulse and in a receiving phase following the transmitting phase is ready to receive high-frequency response signals coming from a responder (26) which transmits said response signals as reaction to the reception of the interrogation pulse. In the damping circuit (24) a damping member (R5, R5, R6) is provided which is adapted to be connected to the antenna resonance circuit and disconnected therefrom. A switching means (T4, T5) on receiving a switching voltage applies the damping member (R4, R5, R6) to the antenna resonance circuit (28).