How to convert dc to ac?

Can anybody tell me how to convert dc to ac i actually want to convert 9volts dc to 9 - 7 volts ac cause i need to supply this ac voltage to a step-up transformer so that it will convert it into 200volts the real problem is when i provide 9volts dc to the step-up transformer it only gives out 41volts in output but when i gave it 9volts ac from another transformer it gives out 200volts ac and that's what i need but i need it to be battery powered so i need to convert the 9volts dc supply from the battery to 9 or less volts ac that's all i want to ask how to do it!

mrmerino2 years ago
First of all, Periods. Second, how could you possibly get a reading on the output on the transformer with DC going in?

Alright, so you need an inverter. rickharris has the right idea, but basically make sure that the equipment you are using can handle the current draw. Instead of using a 9 volt battery, try six AAs. They should be able to supply more current.
samaddon (author)  mrmerino2 years ago
i've just connected the two treminal out from the battery to the secondry wnding which is of 8 volts.the i checked the voltage with a multimeter it shows 9volts DC in 40 volts AC out.
How does that even- what? What the hell? Is anyone else confused?
You need a lot of current. What kind of source are you using ?
samaddon (author)  steveastrouk2 years ago
i am using A 9volts battery!
You can't do it with a tiny little battery like that. You did well to get as much as 40 V from the transformer.
A 9V battery doesn't have a lot of power in it. Trying to use it to produce 200VAC will run it dead in seconds or overheat the battery and cause it to burst open. 9V batteries are best used in small low power projects. Even then it would be better to use 6 AAA batteries rather than a 9V.
Apparently your 9V source isn't putting out enough current for the step up transformer to give you the full 200VAC.
A 9 volt battery - assuming a PP3 isn't going to give anything but milliamps.

Converting DC to AC in a quick dirty way but goo enough for a transformer try a 555 times set to give 50 hz and a suitable power transistor to drive the transformer.