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 circuit was found in a 1967 American documentation. The switching diode (tunnel) used is an...
This sonic control circuit for a small robot turtle was obtained in an American documentation from 1967....
This circuit triggers a load when the sensor detects humidity. The triggering point is adjusted by...