| 摘要 |
PURPOSE:To attain amplification with high fidelity, by forming the titled amplifier that it is hardly subjected to the effect of external circuits even if the 1st and the 2nd transistors(TR) and a variable resistor are located remotely by means of shield wires connecting them. CONSTITUTION:One end of the 1st and the 2nd resistors 17, 18 is connected to the emitter of the 1st and the 2nd TRs 1, 2, and the 1st and the 2nd capacitors 19, 20 are connected in parallel with the 1st and the 2nd resistors 17, 18. The other end of the resistors 17, 18 and the variable resistor 9 are the 1st and the 2nd shield wires 13, 14 made of electrostatic shield wire or coaxial cable. The 3rd and the 4th resistors 7, 8 to determine the current of the TRs 1, 2 are connected between the other end of the resistors 17, 18 and a negative power supply terminal -V. Thus, even when the variable resistor 9 is placed on the operating panel of an oscilloscope and a differential amplifying circuit including the TRs 1, 2 is provided on a circuit board apart from the panel, no switching noise generated at external circuits is given on wirings, allowing to prevent the interference of picture. |
