This circuit was found in an Electronics World of 1968. The transistor can be any general purpose and the double T must be set to R3 for the desired effect.
Suggested by General Electric in an old documentation, this circuit can use modern SCRs and the...
The frequency of this oscillator depends on T, which for the audio band can be a common output...
This circuit has a common configuration widely used in projects on this site. The transistor is...