Adaptor for inter-relating an external audio input device with a standard television receiver, and an audio recording for use therewith

An adaptor for inter-relating an external audio input device with a standard television receiver, wherein said device plays back simultaneously over a single channel both a first carrier and a second carrier, wherein said first carrier consists of a given audio frequency phase-shift-keyed with binary-coded video information so that a first binary value is manifested by said first carrier having a given phase and a second binary value is manifested by said first carrier having a phase of substantially 180.degree. with respect to said given phase, said first carrier persisting with said given phase in those recorded intervals in which all video information is absent, and said second carrier consists of said given audio frequency having a phase which is substantially in quadrature with said given phase, said second carrier being amplitude-modulated by analog audio information;

• said adaptor comprising:
• a video-information channel;
• an audio-information channel, and
• phase-sensitive coupling means responsive to the phase of said given audio frequency applied thereto over said single channel from said device for simultaneously supplying solely said first carrier to said video-information channel and solely said second carrier to said audio information channel.

In an adaptor for inter-relating an external audio input device with a standard television receiver;

• wherein said device plays back a time-division-multiplexed audio information and frequency-shift-keyed binary-coded video information for deriving a serial signal which is applied as the signal input to said adaptor;
• wherein any sequence of video information is immediately preceded by a preamble code comprising a given length of a single one of the frequency-shift keying tones, and wherein said adaptor comprises a video-information channel, an audio-information channel, coupling means for initially coupling said audio-information channel to said signal input, a preamble code detector coupled to said coupling means for continuously monitoring said signal input, and control means coupled to said preamble code detector, said coupling means and said video-information channel for decoupling said audio-information channel from said signal input and coupling said video-information channel thereto in response to the detection of said preamble code by said preamble code detector;
• the improvement for eliminating crosstalk between said channels, wherein said coupling means comprises:
• a normally open gate having its output coupled to said audio-information channel,
• a delay means providing a given delay substantially equal to the duration of said given length preamble code coupled between said signal input and said normally open gate for passing said input signal to said audio channel only after it has experienced said given delay, and
• means coupling said gate to said control means to close said gate in response to the detection of said preamble code.