Abstract: A frequency synthesizer of the phase locked loop type and particularly useful for frequency hopping applications includes means (8) for achieving fast frequency and phase lock. In one embodiment the synthesizer is steered to a new frequency value by a DAC 10 which controls a VCO (5) input voltage. Subsequently, the phase of the synthesizer output is locked to that of the reference frequency oscillator (1) by resetting the feedback frequency divider (6) at the point in time when a rising edge of the reference frequency is detected. In a second embodiment, rapid frequency and phase lock is achieved by resetting the feedback frequency divider (6) on every rising edge of the reference frequency while the feedback loop is disabled, until the detected phase difference between the reference frequency and the divided VCO frequency reaches a minimum value.