Indicated for activation by microcontrollers, this circuit was found in the Radio Electronics magazine of December 1987. The MOSFET can be of any type according to the buzzer.
This sensitive two-transistor circuit was found in the June 1965 Radio Electronics magazine. The...
This circuit, obtained in an old publication, causes a second telephone bell to be played in a...
Found in a1969’s neon lamp documentation, this circuit uses a high voltage transistor. The output...