> 100 W should be ok.
> where to get some design info?
>
> I think about using one 100W car audio amplier and a 100 W
> 110-5 V transfermer.
>
> any suggestion?

        Yup, buy one. Honestly, unless you're doing it for "educational" reasons
the cost of buying one is probably far cheaper (and SAFER) then trying to
build one. TTYL

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