Found in the 1990 special issue of Radio Electronics Experimenter magazine, this circuit uses an automobile ignition coil. Adjustments can be made to suit the coil.
Found in documentation from the 1970s, this circuit uses an oscillator and a display to warn of...
This circuit simulates a low-level siren and can be supplied with voltages from 5 to 15 V....
The filter shown in the figure, using only an operational amplifier, is characterized by allowing 1...