A high-frequency voltage supply system for supplying a multipole mass spectrometer, in particular a quadrupole mass spectrometer, with an HF AC voltage used to generate a multipole field, in particular a quadrupole field, in a secondary circuit excited by means of a primary circuit, comprising a) an HF voltage generator with a synthesizer being implemented for setting with quartz precision and holding the frequency of an AC voltage in the primary circuit according to a frequency value, the HF voltage generator comprising frequency readjustment means, being implemented for ascertaining the resonance case of the secondary circuit or a deviation from the resonance case and, in case of a deviation from the resonance case, for automatically readjusting the frequency of the AC voltage in the primary circuit in such a manner that the resonance case is reproduced and therefore the secondary circuit is held at resonance by automatically readjusting the AC voltage in the primary circuit at resonance, b) frequency provision means for digitally providing the actual frequency value, currently set on the synthesizer, to a computing device, c) HF voltage supply system being implemented as a digital voltage meter for sampling the HF AC voltage in the secondary circuit and for digitally ascertaining a digital measured value, which is a function of this HF AC voltage, as the actual HF voltage, d) whereas the computing device is implemented for calculating a digital AC voltage amplitude setting value as a function of (i) the actual HF voltage value, (ii) a target HF voltage value assigned to a mass to be detected, (iii) the frequency value of the AC voltage in the primary circuit currently set at the synthesizer provided for the computing device, and (iv) the rod radius (r) of a rod-shaped electrode (4, 4', 4", 4"') of the multipole mass spectrometer or of the field radius (r 0) of the multipole field, in response to a frequency change of the AC voltage in the primary circuit set by the automatic readjustment of the frequency and for providing the AC voltage amplitude setting value at the HF voltage generator to set the amplitude of the AC voltage in the primary circuit and e) the HF voltage generator being implemented for indirectly readjusting the HF AC voltage in the secondary circuit with a readjusted HF voltage amplitude, as a function of the AC voltage amplitude setting value, by setting the amplitude of the AC voltage in the primary circuit. a) an HF voltage generator with a synthesizer being implemented for setting with quartz precision and holding the frequency of an AC voltage in the primary circuit according to a frequency value, the HF voltage generator comprising frequency readjustment means, being implemented for ascertaining the resonance case of the secondary circuit or a deviation from the resonance case and, in case of a deviation from the resonance case, for automatically readjusting the frequency of the AC voltage in the primary circuit in such a manner that the resonance case is reproduced and therefore the secondary circuit is held at resonance by automatically readjusting the AC voltage in the primary circuit at resonance, b) frequency provision means for digitally providing the actual frequency value, currently set on the synthesizer, to a computing device, c) HF voltage supply system being implemented as a digital voltage meter for sampling the HF AC voltage in the secondary circuit and for digitally ascertaining a digital measured value, which is a function of this HF AC voltage, as the actual HF voltage, d) whereas the computing device is implemented for calculating a digital AC voltage amplitude setting value as a function of (i) the actual HF voltage value, (ii) a target HF voltage value assigned to a mass to be detected, (iii) the frequency value of the AC voltage in the primary circuit currently set at the synthesizer provided for the computing device, and (iv) the rod radius (r) of a rod-shaped electrode (4, 4', 4", 4"') of the multipole mass spectrometer or of the field radius (r 0) of the multipole field, in response to a frequency change of the AC voltage in the primary circuit set by the automatic readjustment of the frequency and for providing the AC voltage amplitude setting value at the HF voltage generator to set the amplitude of the AC voltage in the primary circuit and (i) the actual HF voltage value, (ii) a target HF voltage value assigned to a mass to be detected, (iii) the frequency value of the AC voltage in the primary circuit currently set at the synthesizer provided for the computing device, and (iv) the rod radius (r) of a rod-shaped electrode (4, 4', 4", 4"') of the multipole mass spectrometer or of the field radius (r 0) of the multipole field, e) the HF voltage generator being implemented for indirectly readjusting the HF AC voltage in the secondary circuit with a readjusted HF voltage amplitude, as a function of the AC voltage amplitude setting value, by setting the amplitude of the AC voltage in the primary circuit.