Abstract: A blocking oscillator which makes use of a javelin fluorescent tube rated 12 V DC, 8 W and with dimension (370�45) mm used for a low voltage lighting was improved upon by redesigning the circuit and the pulse transformer. The blocking oscillator was first experimented on to analyse its performance, to determine the following parameters, the time constant, the pulse duration and the efficiency as well as the turns ratio of the pulse transformer. The results obtained from the experiment showed that the efficiency is low. The circuit was redesigned to increase the efficiency. Therefore, with the turns ratio of 1:1at the (collector) primary and (base) secondary and 1:8 at the (collector) Primary and tertiary (High voltage) winding coupled with the necessary changes in the component values as a result of redesigning the circuit to obtain the pulse duration of 10 �s and time constant of 30 �s. The results obtained from the calculations carried out showed an improvement in the efficiency. The efficiency increased from the previous value of 58.2-93.3%.