This Wien bridge oscillator was found in Radio Electronics from the 90s. The circuit uses the 741 which is a current component. The circuit requires a symmetrical power source.
This circuit, suggested by National Semiconductor, is a tone control (bass and treble) with high...
This circuit from a Japanese publication in 1968 uses germanium transistors from the time like the...
This circuit is from a publication by Newton C. Braga in the United States. The transistor can be...