| 摘要 |
1,247,129. Transistor amplifiers. TEKTRONIX Inc. 25 March, 1970 [25 April, 1969], No. 14440/70. Heading H3T. In an F.E.T. source follower amplifier a highfrequency circuit including a bipolar transistor is connected between the gate and source electrodes of the F.E.T. so that h.f. signals by-pass the internal capacitance 30 between these electrodes. The by-pass circuit includes a capacitor 28 and this is chosen to be equal to an output load capacitance 18, including stray capacitance, and is about 1 pf. The amplifier is supplied via a second F.E.T. 32 connected as shown which acts as a constant current source and provides temperature compensation, and it may be a vertical pre-amplifier in an oscilloscope. |
