Abstract: Tracking of a target by a radar possessing electronically controlled nutan (conical scan) is difficult when the target employs pulse jamming techniques, since pulsing of the jammer at or near the nutation frequency causes the radar to break lock on the target. In the present concept, the lobing reference signals for azimuth and elevation are periodically reversed in phase, the reversals of the two signals bearing a quadrature relationship to one another. By thus reversing the direction of nutation in synchronism with the radar pulse-rate switching signal, the deleterious effects of countermeasures on the radar's angle-tracking capabilities are minimized.