CAFM ADAPTABILITY OF FM RECEIVERS.

CAFM (FM broadcast on a CATV system) is an important medium in addition to off-air broadcast on the concept of VHF/FM signal transmission for hi-fi stereo sound reproduction. It was found that the immunity of direct pick-up from the ambient field, suppression of local oscillation leakage and multisignal intermodulation in conventional receivers were not always satisfied with the adaptability to CAFM in consideration of present technical standards and field data investigated by the writers. Desired specifications for receivers are, at this stage, less than 100 mu V of local oscillation leakage against at least 90 dB/m of ambient field strength and trivial deterioration of the output signal quality with 46 to 60 dB input signal levels. These specifications were proved to be technically achieved, but further study is necessary for improving the technical standards of the cable system itself for FM broadcast. References to English-language sources are in English.