Using a 4046 PLL this circuit recognizes a 1.6 to 1.8 kHz tone by driving an output LED. The circuit is from a Radio Electronics from December 1989.
CUI Current Sensors Mouser Electronics announces in its stock Cui's line of current sensors for...
This TTL module can be used in counter and many of them can be cascaded to counts up to 99, 999,...
This circuit uses a phototransistor as sensor. The changes in the resistance of the transistor,...