We found this circuit in a 1987 documentation. It is a multi-tester with neon lamp and LEDs operating with both low continuous voltage and high alternating voltage.
For reference only, this is the first IF amplifier stage of a common transistor radio from the...
This circuit from July 1975 Radio Electronics uses any operating system with a symmetrical source....
This setting is valid for other transconductance operational amplifiers. The circuit is from...