NMR (Nuclear Magnetic Resonance) capacitor switches allow for adjusting the resonant frequency ranges of NMR measurement circuits by inserting or removing capacitors having different values into the circuits. A change of position of a single switching member is used to change the contact state of at least two capacitors. In some embodiments, at least two pairs of external contacts are disposed at distinct longitudinal levels along a channel, and a slider including multiple longitudinally-spaced capacitors is moved longitudinally within the channel to establish electrical contact between the external contact pairs and different capacitors along the slider. In other embodiments, two capacitor columns are disposed along the channel, and a movable longitudinal member establishes electrical contact between the two columns at different longitudinal levels along the columns. In some embodiments, capacitor covers or intracapacitor blocks are provided to protect the capacitors. An auxiliary inductor may also be inserted into the circuits.