Convert the regular square wave UPS into sine wave

Hi all,


I am a newbie, I do need a true sine wave backup 220VAC for some of the induction appliances. Since I have burned out a desk fan by use long time with the APC computer UPS.
Some one if gonna help me to hack the a.m. UPS into sine wave with the simplest way. I am electrical man but getting the hobby of electronic so much.

Thanks so much

CSV

PS: If the thread title has been existed, please do something to comply and PM to me.

I think the short answer is...no! If it were "simple", they would be selling them at the same price as your APC.

Ken