A power amplifier system comprising: a first amplifier circuit having a first output terminal; a second amplifier circuit having a second output terminal; and a power combiner circuit (202, 302, 402, 502, 700) coupled to each of the first and second amplifier circuits (206, 208) and having a first microstrip transmission line component (232, 702), a slotline formation (234, 304, 404, 504, 704), and an additional coupling component that is capable of being at least indirectly coupled to a load, wherein first and second locations along the first microstrip transmission line component (232, 602, 702) are respectively short-circuited to the first and second output terminals; and wherein the slotline formation (234, 304, 404, 504, 704) extends between a first position proximate the first microstrip transmission line component (232, 602, 702) and a second position proximate the additional coupling component (236,306,406,706); wherein the first microstrip transmission line component (232, 602, 702) and additional coupling component (236,306,406,706) are electromagnetically coupled by way of the slotline formation (234, 304, 404, 504, 704); and wherein a further position, at or proximate to which the first microstrip transmission line component (232, 602, 702) crosses the slotline formation (234, 304, 404, 504, 704), is a combining node, wherein a combining node impedance associated with the combining node is matched to a load impedance of the load, wherein the slotline formation (234, 304, 404, 504, 704) serves as a quarter wave slotline, and wherein the additional coupling component (236,306,406,706) is galvanically isolated from the first microstrip transmission line component (232, 602, 702). a first amplifier circuit having a first output terminal; a second amplifier circuit having a second output terminal; and a power combiner circuit (202, 302, 402, 502, 700) coupled to each of the first and second amplifier circuits (206, 208) and having a first microstrip transmission line component (232, 702), a slotline formation (234, 304, 404, 504, 704), and an additional coupling component that is capable of being at least indirectly coupled to a load, wherein first and second locations along the first microstrip transmission line component (232, 602, 702) are respectively short-circuited to the first and second output terminals; and wherein the slotline formation (234, 304, 404, 504, 704) extends between a first position proximate the first microstrip transmission line component (232, 602, 702) and a second position proximate the additional coupling component (236,306,406,706); wherein the first microstrip transmission line component (232, 602, 702) and additional coupling component (236,306,406,706) are electromagnetically coupled by way of the slotline formation (234, 304, 404, 504, 704); and wherein a further position, at or proximate to which the first microstrip transmission line component (232, 602, 702) crosses the slotline formation (234, 304, 404, 504, 704), is a combining node, wherein a combining node impedance associated with the combining node is matched to a load impedance of the load, wherein the slotline formation (234, 304, 404, 504, 704) serves as a quarter wave slotline, and wherein the additional coupling component (236,306,406,706) is galvanically isolated from the first microstrip transmission line component (232, 602, 702).