| 摘要 |
PURPOSE:To obtain a signal switching circuit which is suited to a miniature integrated circuit, by allotting the wave detection output voltage of the ACC loop to each current Miller circuit to carry out the channel switching and at the same time supplying each output to the integrated circuits having the same constant each. CONSTITUTION:The output with which the burst signal is detected is supplied to the base of the transistor Q1, and the switch signals which switch mutually according to each head are supplied to the bases of the transistors Q6 and Q7. Then the output of each head is selected by the switch signal to obtain again the continuous control voltage ouput. For this purpose, the output of the current Miller circuit is earthed with every field and via the switching transistors Q6 and Q7. At the same time, the diodes D1 and D2 are provided between the loads and then biased adversely when the loop is cut off. |
