This is a classic FM amplifier IF amplification stage configuration. The circuit is from a 1980s documentation. CN is the neutralizing capacitor.
Found in a 1990s William Sheets, this automatic gain control for audio amplifiers uses...
The power supply shown can supply voltages of approximately 0 V to 12 V with a maximum current of 4.5 A,...
The consumption of this circuit in the standby condition is only 1 uA. The circuit must be...