Found in a 1980s American documentation, this circuit appears with variations elsewhere in this section. The circuit activates a relay according to the supply voltage.
This circuit generates a pulse of duration determined by the capacitor when an object interrupts the...
This “people detector” with pyroelectric sensor was found in the April 1991 issue of Radio...
This wideband circuit with the 4046 PLL was found in the December 1989 Radio Electronics magazine. The...