A double Blumlein pulse generator is constructed using a coaxial cable. This power supply is capable of providing a voltage up to 20 kV across a matched load and 40kV across an open load with a charging voltage of 10 kV. It is designed to provide a pulse width of 110ns. A rise time of ∼10ns is obtained with present spark gap. A rotating spark gap is also designed and constructed to get a pulse repetition rate of 25Hz. Although, in the present work this pulse generator is used to study the streamer discharge in air, it is useful in many other applications also.