Harold Kapp, what on earth? Hook directly into the mains? That would be extremely dangerous!!!! A great way to get electrocuted or burn your house down. DO NOT do that. If all the lights in the house dim, it's probably the main power feed into the house is a little undersized. there's not a whole lot you can do, except put in a bigger meter/main and have the power company put in a bigger service. Lots of $$$. I would put a UPS on a PC if you have one, and good surge protectors on anything electronic. Many older homes have this problem.