| 摘要 |
PURPOSE:To obtain automatically a steady oscillation frequency, by securing an automatic correction for the input/outpt phase difference of an amplifying circuit or feedback circuit and then giving an automatic correction to the input/output phase difference based on the above correction as well as set the input/output phase difference of the feedback circuit at a fixed level. CONSTITUTION:The feedback circuit 1 and the amplifying circuit 2 are connected in parallel to form an automatic frequency correction type oscillator. At the same time, the external control phase correction circuit 3 using the PLL and others is provided between the circuits 1 and 2. Then the phase comparator 4 is connected in parallel to the circuit 1, and the pulse having a duration corresponding to the amount of advanced phase is delivered with every cycle to the output terminal X if the phase of the input terminal B gains compared with the input terminal A. While the pulse having a duration corresponding to the amount of delayed phase is produced at the output terminal Y in case the phase loses. In such way, either output is applied to the rectifying circuit 5A or 5B in the control circuit 5, and this output is applied to the circuit 3 via the additional amplifier 5C. Thus the phase shift of the circuit 2 can be corrected automatically. |
