| 摘要 |
PURPOSE:To stabilize the DC level of the output of detection, by integrating the signal with the multiplex sound subcarrier received a peak wave detection through a Miller integral network and then feeding this output of integration back to a differential amplifier. CONSTITUTION:The aural subcarrier input is applied to a wave detection circuit consisting of the transistor 16, diode 19 and capacitor 20 after passing through the differential amplifier 9 comprising the transistors 3, 4 and 5. On the other hand, the output of the amplifier 9 is integrated by a Miller integral network consisting of the transistors 29 and 30, capacitor 33 and resistance 32. The output of integration is fed back to the base of the transistor 3 of the amplifier 9 via the resistance 35. In such constitution, the variance can be eliminated for the output DC level of the amplifier 9. |
