Comcast's purchase of majority ownership in NBCUniversal from GE is proving to be a good move. Comcast, the largest U.S. cable company, posted a 16 percent increase in second-quarter profit Tuesday in part because of rising sales at NBC Universal.

GE sold 51 percent of NBCUniversal to Comcast in a deal completed earlier this year. Broadcast television revenue for NBC was $1.7 billion in the quarter, up from 19 percent the previous year. NBC's broadcast-TV advertising revenue rose 6.8 percent to $1.11 billion despite the fact that prime time programming on NBC trailed competitors in the ratings.

Net revenue for Comcast climbed to $1.02 billion, or 37 cents a share, from $884 million, or 31 cents a share from the previous year. The Philadelphia-based company said excluding some costs, profit was 42 cents a share, beating the 41 cents a share estimate by analysts.

Comcast added users to its Internet business, increased revenue at NBC, and reduced video-subscriber losses.

Comcast lost 238,000 video subscribers in the second quarter, 10 percent less than the company lost in the same period one year ago. In broadband, Comcast added 144,000 subscribers, an increase of 22 percent from the previous year.

"Comcast is pulling all of the right levers," said Paul Sweeney, an analyst at Bloomberg Industries in New York, before the results were released, in an interview with Bloomberg. "They're getting ad revenue at NBC and the cable stations, they're buying back stock and they're paying a dividend to shareholders."

The acquisition of NBC has been perhaps the biggest boost for Comcast, providing diversification and growth beyond the company's Internet and cable subscription businesses. In all, NBC contributed 36 percent of Comcast's sales in the quarter.

"I am...pleased with the performance of NBCUniversal, which posted double-digit revenue growth in each of its segments," said Brian Roberts, Comcast chairman and CEO, in a statement. "We are confident that the strategic investments we continue to make at NBCUniversal and Comcast Cable are strengthening our business, driving profitable growth and building value for our shareholders."

Comcast has now beaten Wall Street's expectations for the past four quarters.