This circuit generates short pulses. The transistor can be a 2N2222 or BC548 and the frequency is given by the resistors and the capacitor that can be changed.
The MOS field effect transistors of this circuit are not very common, as it is a project from the...
This old circuit uses na operational amplifier not easy to find in these days. But the circuit can be...
This circuit consists of an astable multivibrator whose frequency changes according to the light...