Found in American 90’s documentation, this circuit generates 300 Hz depending on the capacitors used. These components can be changed to obtain other frequencies.
Radio Electronics magazine published in a 90's issue this simple alarm that can use any general...
This circuit is from the 2005 Linear Technology Application Manual. The circuit must be powered by 5...
We found this circuit in a 1969 General Electric documentation. The circuit uses transistors of the...