A fluid-applying device for applying a fluid to a teat of a dairy animal. Each member of the set has at least one electric feed-in block, which is connectable to the locally available system voltage and from this generates an output voltage, which is the same for all members of the set and is lower than or equal to the lowest system voltage, for which a member of the set is designed. The phase shifting means are arranged to provide a phase shift of substantially 180 degrees. The DSP is a standard DSP avoiding the need for any hardwaresoftware modification of the DSP to perform the test mode. Constrained beamforming adaptive monopulse is used to simultaneously place nulls in both the sum and difference beams toward jammers while maintaining the monopulse ratio for accurate angular measurement.