modulation classe B

CONT: The transmitter is capable of operating on any frequency between 14 and 100 meters, and 112.5 and 150 meters and employs class B modulation on the final power stage.
CONT: Collins radio telegraph equipment ... used ideas that were later widely adopted in the radio field. These included multiple pretuned frequency bays, which allowed the operator to make quick frequency changes, and class B modulation, which permitted large audio power from relatively small tubes.