This 800 Hz sinusoidal oscillator was found in a 1970s American documentation. The transistor supports a modern general-purpose equivalent. The frequency is given by the RC network that can be changed.
This circuit indicates when the voltage of a 12 V battery is low. With changes, for example, the...
In this interesting circuit, a common relay is used as a vibrator to obtain high voltage with a...
Here we show an oscillator that uses an LC network. The upper limit depends on the power-supply...