| 摘要 |
PURPOSE:To facilitate switching operation and prevent a waste of electric power by connecting audio outputs of video equipment and acoustic equipment to external speakers through a switching circuit and operating the switching circuit associatively with the opening/closing operation of the power source of the acoustic equipment. CONSTITUTION:Changeover terminals 17 and 19 of switches S2 and S1 of the switching circuit F are connected to output terminals 5 and 8 of the video equipment A and changeover terminals 18 and 19 are connected to output terminals 9 and 12 of the acoustic equipment B. Common terminals 21 and 22 of the switches S1 and S2 are connected to input terminals 13 and 15 of external speakers C and D. Further, negative-side terminals 6, 7, 10, 11, 14, and 16 of those equipments are connected to an earth terminal 23 together. A relay E is energized associatively with the on-off operation of the power source of the acoustic equipment B and the switches S1 and S2 are connected to the terminals 18 and 20, or 17 and 19. Consequently, driving sources of the external speakers are easily selected and when the acoustic equipment is not used, its power source is turned off automatically to prevent a waste of electric power. |
