This alarm oscillator was found in the December 1974 issue of Radio Electronics magazine. The power transistor must be equipped with a good heat sink. The Frequency basically is given by C1.
This circuit selects a signal at a frequency determined by the double T. The NPN transistors can...
The frequency of this oscillator depends on the capacitors, being able cover the range between 1...
This is the traditional configuration of an inverter amplifier with operational. The operational...