LM339N : Integrated circuit 14 pin DIP quad voltage comparator. Substitute for BA10339 low power quad voltage comparator
ULN2803A : Integrated circuit 18 pin DIP Switch Matrix Driver
SN74LS240N : Buffer/Line Driver 8-CH Inverting 3-ST Bipolar PDIP-20
SN74LS244N : IC CHIP BUFF/DVR TRI-ST DUAL 20DIP
SN74LS374N : D-TYPE POSITION TRIGGER SINGLE 20-PIN PDIP
74HC237N : NSC 16-PIN DIP
