This specification covers Teletypewriter Set Mf.-522( )/G?C which -is desimed t o provide a radio t e d n a l capable of SimultaneOUSlY transmitting md receiving narrow sh-ift teletvpe(85 Hz), wide s h I f t teletype(850 Hz).,frequency diversity teletype(85 Hz),simultaneaus voice and narrow shift teletype(85 Hz), or voice only.