Regulation 74 Experimental radio service(1) An experimental radio service shall make transmissions that are necessary and directly related to the conduct of the experiment in respect of which a licence is granted under these Regulations.(2) The holder of an experimental radio service licence shall ensure that energy emitted from the transmissions during the transmission does not cause harmful interference with other telecommunication services.(3) Where the holder of an experimental radio service licence becomes aware that a transmission is causing harmful interference to other telecommunication services the holder of the licence shall cease the transmission and shall not resume the transmission until the holder of the licence is satisfied that no harmful interference will be caused upon resumption.(4) Unless expressly authorised by the Authority, an experimental radio station shall not be used(a) to retransmit signals to any other station except to a station that is integrated in the experiment;(b) to transmit programmes intended for public reception; or(c) to render any other telecommunications service.(5) A person who holds a valid certificate issued or recognised by the Authority shall make or supervise the making of any adjustment of a transmitter in an experimental station which may affect the proper operation of a radio station.(6) The Authority may grant a licence in respect of two main classes of experimental stations, namely(a) an experimental research station, and(b) an experimental developmental station unless otherwise determined by the Authority.(7) The Authority may grant a license under sub-regulation (6) (a) to a person qualified to conduct experiments utilising radio frequencies (a) for scientific or technical radio research not related to an existing or proposed service,(b) for communication in connection with research projects where existing communication facilities are inadequate,(c) for the development of equipment for using in an existing service, or(d) for the development of equipment or technical operational data directly related to the use of radio.