The first objective for Lab 1 was to design a circuit in which an LED illuminated only if two mechancial switches were closed. Our team intially thought to use a AND gate to accomplish this, however, the only logic gates available were NAND and NOR gates. We constructed the AND function out of three NOR gates as shown in the picture. Two pull-up resistors (5 Kohm) were used to supply high voltage to the NOR gates when the switches were closed. The output current from the logic gate went to the transistor base, which closed the switch and allowed the LED to light up.
Bench testing showed our LED worked well when 1.5V and 40mA was applied. Calculations for sizing resistors R3 and R4 was determined as shown in the schematic. 
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