This timer circuit provides an output cycle which is on for one minute and off for five-minutes. The 7555 timer (IC1) produces a positive pulse about once every 60s to clock a 4017 divider (IC2). The '0' output of IC2 is high for 60 seconds and drives Q1 and the relay during this period. On the next clock signal from IC1, the '1' output goes high and the '0' output goes low and the relay is off.
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