You can make this Transistor timer easily for driving a relay for few seconds to few minutes. It is too simple and uses only two transistors and few other passive components. Just press on the switch to start relay and after the time ends, relay will switch off. You can also set the time using a Trimpot.
Don’t miss your favorite TV programme or don’t forget to irrigate garden. This clock controlled circuit will actuate a relay to switch on the AC load to perform the function at the right time. Operation of the circuit is simple. It receives the triggering pulse from the buzzer terminals of the clock and an SCR triggers to activate the relay. The only drawback of the circuit is that, it is necessary to switch off the load manually by turning off the power. You can do experimentation to make an automatic operation also.