This is a surprise. Dish Network CEO Charlie Ergen announced today that he’s calling it quits. He’ll turn the reins of the No. 2 satellite company over to longtime consumer electronics executive Joseph Clayton next month. Ergen still controls Dish stock and will remain its chairman. Clayton had been chairman of Sirius Satellite Radio, and earlier helped to revive RCA as a consumer brand.

Ergen’s recent decision to buy Blockbuster out of bankruptcy seemed to provide just the kind of challenge that would intrigue an executive who became a multi-billionaire by outsmarting and outlasting more powerful rivals including Rupert Murdoch. But while Ergen had become one of the most durable fixtures of the media business in his 31 years at the helm of the company he founded, he also provided plenty of signals that he was ready to pull back from the daily grind. Several years ago he drastically cut back on public appearances. He’s almost invisible aside from presentations he pretty much has to make to reassure Wall Street analysts and his own sales teams.

In 2009, Ergen gave up the CEO title at EchoStar, the unit he separated from Dish to develop electronics devices for consumers and the satellite company. Lately he has questioned whether the cable and satellite business model — selling packages of networks to consumers — can survive as Internet services such as Netflix make it easy for people to watch individual shows on demand. Ergen also has said that he’d let someone else run Dish once the company had found its footing. He apparently thinks Dish has as its stock spiked following the settlement of its five-year DVR patent infringement dispute with TiVo, and its report of solid quarterly results helped by a recent increase in subscription prices.