This small control for DC motors up to approximately 1 A uses an operational amplifier that admits equivalent. The transistor can be TIP29 for currents up to 1 A or BD135 for 500 mA.
An E or AND gate can be constructed based on common diodes. In the case, the diodes are for...
This circuit is from an 80's publication. It makes use of small 6 V x 50 mA incandescent lamps....
When S1 is closed, the L1 lamp turns on and the L2 lamp turns off. The circuit is powered...