摘要 |
A muting circuit for a television receiving set comprises a mute-judging part, a mute key input, an acoustic output circuit, a caption-judging part, and a caption key input. The mute-judging partenters a mute ON and a mute OFF state alternately every time it receives a mute key input signal. The acoustic output circuit reduces the sound output level to zero decibels at the mute ON state, and restores the sound output at the mute OFF state. The caption-judging part enters a caption ON state and caption OFF state alternately every time it receives a caption key input signal while it enters a caption ON state if the mute-judging part enters a mute ON state. Thus, in the mute ON stated the closed caption is displayed on the screen.
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