Found in the May 1975 issue of Radio Electronics magazine, this circuit turns on after a certain amount of time. This gives the owner of the premises time to leave before the alarm is activated.
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...