9v DC to 9v AC

[amer1337]

is there a simple circuit to turn power from a 9v dc battery pack to 9v ac to use with a small cheap speaker system? or do the speakers have to turn the ac into dc to use it so i can find out where i need to put the dc?

[Antioch]

Just wondering if you know the difference between DC and AC sources.

[GigaForce310]

The short answer is no.

The somewhat longer answer is that you need a boost circuit and inverter to get the 9 VDC to 9 VAC. These are very complex and difficult circuits to make.

[DvBoard]

what are you attempting to power?

[Super Nade]

What are you attempting to build? There is a chip that does it, but maybe you can tell us what your goal is?

[freakdiablo]

he said it was to power a small speaker system. What for though? wanna get amplified speakers for a laptop or something?

[Skeith]

The short answer is no.

The somewhat longer answer is that you need a boost circuit and inverter to get the 9 VDC to 9 VAC. These are very complex and difficult circuits to make.
not neccicarily. It just depends on how accurate of an AC waveform he wants. For a crude 60Hz 9v AC squarewave all you would need is a fast acting H-bridge circuit, a 60Hz osscilator that could be from an NE555 and a simple signal inverter. (truns a high to a low etc.) It wouldent be highly reliable but would produce a crude 9v peak to peak square wave AC voltage that could be used in situations where accuracy isnt a big deal such as running it through a simple capacitor cascade to bring the voltage up to 18v DC.

Speakers if they require a AC input will end up rectifying it (turning it into DC) shortly after it is pulled into the device. The speakers would probably run on a 9v DC input directly on the jack if they have a full wave bridge for rectification. If you trace the citcuit on the board you should be able to apply 9v DC after the rectifier to power it. If its a full wave you can plug it directly into the jack.

You arent planning to run the speakers off of a 9v battery are you? If you are I suggest you find a better power source like 6 alkaline C cells or 7 NiMH 2500mah AA cells. 9v batteries can only supply about 120mah due to their internal resistance and will die very quickly. They are only usefull in low drain applications such as alarm clock, smoke detector etc where the device will draw a very low current for a long period as opposed to speakers where - depending on the wattage - the current can reach in excess of 2Amps.