In one embodiment the invention provides a radar trigger and pretrigger generator which determines the inherent component time delay through the radar modulator and transmitter (10) during a first cycle of operation. During the next cycle of operation, a pretrigger pulse is generated after a time corresponding to the previously measured delay and a trigger pulse is generated after a time corresponding to an operator selectable delay. The trigger pulse is used to trigger the radar modulator (10) which, in effect, permits the operator to control the elapsed time between the pretrigger pulse and the transmitter firing in a fashion which is completely independent of circuit delay variances through the radar modulator and transmitter.