CBS may at long last have an ad-supported, basic cable channel of its own. Published reports over the weekend said that the company has bought a 50-percent stake of the TV Guide Network from JPMorgan Chase's One Equity Partners for $100 million. That would represent a fire-sale price. Lionsgate acquired the channel from Macrovision in 2008 for $295 million, then sold half of it to One Equity Partners and entrepreneur Allen Shapiro for $123 million a year later. The channel comes with a drawback -- its distribution deal with cable providers stipulates that it offer a scrolling program guide, which eats up a huge part of the screen and is something that has been rendered outmoded by most DVRs, which offer their own interactive TV guides.