A new detector using an externally driven tuned circuit has been developed for use in ion cyclotron resonance spectroscopy experiments. Based on the ``Q-meter'' circuit, this detector will operate at frequencies greater than 1 MHz at rf levels less than 1 mV. Operation in the frequency range 1–15 MHz allows the use of higher magnetic fields for more efficient storage of low mass ions in the trapping mode of operation. In the frequency range 2–6 MHz electrons can be detected in the ion cyclotron resonance cell by their resonant motion in the trapping plane.