We found this circuit in documentation from the 1980s. The transformer is of the low voltage type with a 1: 3 turn ratio and the transistors can be of general-purpose types.
This integrated generates all the higher octave frequencies of a common keyboard when a clock...
This circuit was found in a Popular Electronics from the 90s. The frequency depends on the...
This circuit can be controlled by an external signal which allows its use as a shield. The circuit...