A simple timer built around the popular 555 Integrated Circuit. The timer enables the output when the power is applied to the circuit and disables it after the preset time interval. You can adjust the timer from a few seconds to the maximum of 10 minutes. The circuit provides a 9 to 12V DC / 50 mA output (depending on the supply voltage used) which can be directly connected to a 9V or 12V DC relay .