| 摘要 |
PURPOSE:To pick up an oscillation output without adverse influences upon the oscillating operation by using a differential buffer amplifier and a pair of base- grounded transistors TRs to hold well isolation from a principal part of an osicllating circuit. CONSTITUTION:Oscillation is performed by TRs 1 and 2 and a resonance circuit 14. Since bases of TRs 1 and 2 performing the oscillating operation are connected commonly to bases of TRs 25 and 26 constituting the differential buffer amplifier, the oscillation output is taken out to emitters of a pair of base-grounded TRs 31 and 32, a mixer, etc. through collectors of TRs 25 and 26. Further, the oscillation output is taken out to a PLL system from the collector of the TR31. Since TRs 25 and 31 have constitution like what is called a cascode amplifier, this device is superior in isolation. |
