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This 9-minute timer can be used to control lighting in the toilet or bathroom. The timer is started by pressing S1 and stopped by pressing S1 again. If you forget to turn it off, the controlled light will turn off after nine minutes. If you need the light to be on continuously and non-stop, you need to press S1 (turn on) then S2 (cancel timer) within 9 minutes and in this case the light will stay on until you turn it off with S1. IC1 is a dual flip-flop 4013.
The flip-flop IC1a is turned on and off by switch S1 and the relay control is switched by FET Q2. IC1a controls IC1b which is connected as an RS flip-flop to turn IC2, the 4060 oscillator/divider, on or off. Its time interval is determined by the components at pins 9, 10 and 11. The relay must have Contact composition. and they are connected in parallel to an existing wall switch.