Up to six lights can be sequentially flashed using this circuit. LED1 through LED6 can be replaced by optocouplers (MOC3010
, etc.) to control 120-Vac loads via triacs. Ul generates pulses that clock the shift register mode up of the six D flip-flops in the CD 40174. By SI A -B, the register can be programmed either ON or OFF (low or high) and then switched to run in the programmed sequence. S2 clears the program.