| 摘要 |
PURPOSE:To easily detect a signal source in a digital audio signal channel by inserting an audio sample data and an identification signal to the digital audio signal. CONSTITUTION:A digital audio signal received by an insertion circuit 50 is fed to a format decoding circuit 54 via an input connector 52, in which an identification signal of a narrow band width in the digital audio signal is separated and also an incoming identification audio signal is eliminated. A substituted signal is inputted to a microphone 44 and stored in a memory 20 and a format coding circuit 16 inserts a new audio signal in a proper timing. The incoming identification audio signal is stored in the memory 20 through signal path from the circuit 54 to a selector 18. Even without the circuit 54, the digital audio signal is fed directly to the circuit 16 via the connector 52. Thus, the signal source of the audio signal channel is easily detected. |
