Patent ID: 7723988

Claim:
A method for operating a magnetic resonance (MR) detection configuration for investigation of a spin system, the configuration having at least one RF resonant circuit with an inductance having a high impedance point and a reactive transformation circuit connected between the high impedance point and a low-impedance connecting point of the RF resonant circuit, the reactive transformation circuit functioning as an impedance transformer, the configuration also having an RF line with a first connecting point connected to said low-impedance connecting point and a second connecting point, the RF line having a characteristic impedance, a preamplifier module connected to the second connecting point of the RF line, the preamplifier module having at least one passive damping impedance and switching means for connecting the passive damping impedance to the resonant circuit during a damping and/or transmitting process, an RF receiver for receiving signals from the spin system, and an RF transmitter, the method comprising the steps of: a) transmitting, during a transmission time period, RF pulses from the transmitter to the RF resonant circuit to excite the spin system; b) terminating the transmission time period by stopping transmission of the RF pulses to the RF resonant circuit; c) initiating, immediately following step b), a damping time period; d) controlling, during step c), current flow through the passive damping impedance to optimise rapid damping of residual current in the RF resonant circuit; e) blocking current flow through the damping impedance to terminate the damping time period; f) initiating, immediately following step e), a receiving time period; and g) detecting RF signals from the spin system during step f).