Each System 9 configuration includes the ATW-R900a receiver and either a body-pack transmitter or handheld microphone/transmitter. The ATW-R900a is a non-diversity, single-channel receiver with advanced dipole antenna design for extended operating range, which improves operation by providing a ground element in addition to the usual signal element. The ATW-R900a also offers volume control along with AF Peak, RF and Power indicator lights.