A power modulator comprises a plurality of switched pulse generator sections (22), a power supply arrangement (10), and a transformer arrangement (30). A switch control (24) is connected to said plurality of switched pulse generator sections (22) for providing control signals for turning on and/or turning off them. The switch control (24) is arranged to provide control signals for turning on and/or turning off switched pulse generator sections of a first subset at a first time instant and to provide control signals for turning on and/or turning off switched pulse generator sections of a second subset at a second time instant, different from the first time instant: The second subset is different from the first subset.