| 摘要 |
PURPOSE:To make it possible to obtain a great attenuation factor by constituting a split in which the collector dynamic internal resistance of a transistor is connected to a fixed resistance in series. CONSTITUTION:When a resistance supplying a DC current to the collector of transistor 6 is not connected another circuit, any DC current flows through the collector at all, but the collector is held at a DC positive voltage of about 10mV. Once an AC voltage is applied to the collector, the AC current flows by current dynamic collector internal resistance. Therefore, the ratio of output 5 to an input to terminal 1 can be obtained as the split ratio of fixed resistance 2 to the dynamic collector internal resistance of transistor 6. Consequently, an AC waveform variable attenuator can be obtained which has a broad-range attenuation factor. |
