This circuit was obtained from an American 1980s documentation. The frequency depends on the crystal and the circuit may be a PNP that reaches the generated frequency.
This oscillator with signal amplitude adjustment generates a 6.5 Hz signal with the values of the...
We found this circuit for guitar training in an English documentation from 1989. The components are from...
This circuit was found in a Hands On Electronics from the 90s. The circuit does not need a...