This 1000: 1 voltage-controlled filter circuit was found in an Electronics Today International in a 1980s edition. The circuit is based on components of the time.
Found in a 1980s documentation, this amplifier uses an integrated circuit of the era. The RLC...
This interesting experimental and didactic configuration was found in a 1977 Radio Shack...
This circuit for a frequency of 40 kHz was found in an old Electronic Design. There were no...