I've been running a Xantrex Prowatt, which is a modified sine wave, to run my LCD TV, DVD and Satellite receiver with no problems. I run a 1750 watt because it also powers my air conditioner and refrigerator. The 250 watt has a standby draw of <0.1 A.
http://www.xantrex.com/web/id/14/p/1/pt/8/product.asp
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