In this note a new TEM junction switch is described which is based on the three-port junction circulator. Microwave switching is achieved by applying a current waveform through a single wire loop inserted in each of the ferrite disks. In this way the demagnetizing fields of the ferrite shape and the eddy currents in the junction housing are eliminated. The magnetic energy is now determined by the inductance of a single wire turn and is extremely small. The switch can either be continuously modulated by a square current waveform or can be latched by short current pulses between the two remanence states of the closed ferrite shape.