,This part, which shall be used in conjunction with I EC Publication 244-1 and, if applicable with other parts, describes the conditions and methods to be used to measure the quality of the .signal at the output of the transmitter :The methods are applicable to ; amplitude-modulated transmitters with full , carrier, either for radiotelephony or sound broadcasting- amplitude-modulated transmitters with reduced or suppressed carrier, either for single-channel-J- ;or multi-channel radiotelephony with not more than four channels *.frequency-modulated transmitters for monophonic sound broadcasting- In certain cases, they may also be used for amplitude-modulated transmitters with reduced or .suppressed carrier for multi-channel voice-frequency telegraphy