We have excited a passive LiNbO3 whispering gallery resonator with an external mode-locked laser. This
leads to a phase-coherent excitation of several modes of the resonator. The repetition rate is tuned to an
integer submultiple 1/N of the free spectral range of the resonator. The output rate of the resonator is
equal to the input rate multiplied by N, showing frequency multiplier functionality. Impact of nonlinearity
and of dispersion is minimized by low power level and limited bandwidth of pulses. We show that pulsed
ringdown can be measured by modulating the input pulsed train. Quality factor is measured both from CW
transmission and from the pulsed ringdown.