how to convert dc voltage into higher dc voltage using transformer???? i am tring to convert 9 volt dc into 120 volt dc , and i ve to use transformer ,,, the problem is the transformer must have input ac voltage as it work on flux variation . i think the solution is to convert the input dc into ac and then use bridge rectifer at the output to convert it agine into dc ,, but how can i convert the input dc into ac ???????