SELECTIVE AMPLIFIER Russian patent published in 2012 - IPC H03F3/00 

FIELD: radio engineering.

SUBSTANCE: selective amplifier has a signal source (1), a first input transistor (2), a first current stabilising two-terminal device (3), a first power supply bus (4), a second power supply bus (5), a second input transistor (6), a first load resistor (7), a second current stabilising two-terminal device (8), a first balancing capacitor (9), a first frequency setting resistor (10), a second balancing capacitor (11), a third input transistor (12), a fourth input transistor (13), a third current stabilising two-terminal device (14), a fifth input transistor (15) base, a voltage source (16), a fourth current stabilising two-terminal device (17), a third balancing capacitor (18).

EFFECT: high Q-factor of the amplitude-frequency curve of the amplifier and its voltage gain at quasi-resonance frequency f₀.

2 cl, 11 dwg