A method for regulating radio frequency (RF) signals in a nuclear magnetic resonance (NMR) system, comprising a spectrometer, a control loop, and an NMR probe head with RF components (BE, LE, BK), wherein the spectrometer comprises a transmitter that transmits RF signals at measuring frequencies with a transmission power (PS), the NMR probe head contains an RF oscillating circuit, and the RF oscillating circuit comprises an RF coil (LE), is characterized in that the control loop controls the duration and/or the phase and/or the power of the transmitted RF signals. Measurement of a parameter is performed by means of the NMR probe head, via which parameter the current in or the voltage across one of the RF components (BE, LE, BK) can be determined, and the transmission powers (PS) and/or the phases and/or the duration of the RF signals are regulated in dependence on the measured parameter. Any occurring losses can thereby be compensated for without reducing the pulse duration.