This Hughes circuit is from 1968. Equivalent modern components can be used. The input impedance is 1000 M ohm.
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,...