hi all of you it is my another project called water tank alarm that will sounds like birds when water tank is full and it will stops automatically when the pump is set off .it will reduce the over flow of water tanks in our homes.
transistor BC 547 *2
BC 557 *1
resister 1 k *2
capacitor 473 (.047) *2
10-15 inch of strong copper or iron wire
9 volt battery
copper winding wire (to make a audio transformer )