SELECTIVE AMPLIFIER Russian patent published in 2013 - IPC H03F3/00 

FIELD: radio engineering, communications.

SUBSTANCE: selective amplifier comprises a current input (1), connected with a collector of an input transistor (2), the first (3) source of auxiliary voltage, connected to the base of the input transistor (2), the first (4) and second (5) frequency-setting resistors, the first (6) correcting capacitor, the first current-stabilising dipole (7). The collector of the input transistor (2) is connected with the first (8) bus of a supply source via the first frequency-setting resistor (4) and is connected with the common bus of supply sources (10) via serially connected second (AND) and the third (12) correcting capacitors, between the emitter of the input transistor (2) and the base of the additional transistor (14) there is a forward-biased p-n transition (15) connected, between the potential output of the device (13) and the base of the additional transistor (14) there is the second (5) frequency-setting resistor, the first correcting capacitor (6) is connected between the emitter of the input transistor (2) and the emitter of the additional transistor (14), the first (7) current-stabilising dipole is connected between the base of the additional transistor (14) and the second (9) bus of the supply source, the emitter of the additional transistor (14) is connected to the second (9) bus of the supply source via the second (15) current-stabilising dipole.

EFFECT: higher quality of selective amplifier amplitude-frequency characteristic and its amplification ratio by voltage at quasiresonance frequency f₀.

3 cl, 7 dwg