Found in American documentation from 1969, this circuit uses logic inverters to obtain sequences of 4 pulses. The circuit can be used as a shield.
This car alarm was obtained in a Signetics documentation from the 1980s. The circuit uses the 555...
The frequency of this circuit can be varied from zero. The circuit uses the CMOS 4046 and was...
This simple binary counter triggers two LEDs according to the number of pulses applied to the...