a hand - held or portable diathermy apparatus is disclosed comprising a housing , a battery power supply preferably within the housing , and at least one electrode carried by the housing . the apparatus includes a radio frequency power generator for generating an oscillatory current ranging between about 1 kilohertz and about 20 megahertz , and supplying this oscillatory current to the electrodes . a manually operated switch is carried by the housing for selective energization of the radio frequency generator whereby , upon energization thereof , the apparatus is capable of being cycled several times outputting up to about 20 watts of power for up to 20 seconds or more on each cycle .