A Rotary Switch sets the timer according to six classified Photo-types (see table). A Photo resistor extends the preset time value according to sunlight brightness (see table). When preset time ends, ...

P1 will stop the timer if required. LED D1 is optional and can be useful to signal relay operation when the load is placed far from the timer. Parts: R1 – 10M 1/4W Resistor R2 – 4K7 1/4W Resistor R3 – ...

This simple alarm timer circuit is made with 4060 which has an integrated oscillator with a good stability with a relatively wide frequency range. In the circuit diagram the oscillator frequency is ...