Comcast Corp's quarterly earnings beat Wall Street expectations on a better-than-expected rise in Internet and phone subscribers and advertising sales growth at its NBC Universal joint venture.

The No. 1 U.S. cable operator 144,000 high-speed Internet customers and 193,000 phone customers. Analysts at Collins Stewart had forecast additions of 120,000 Internet customers and 190,000 phone customers.

But the Philadelphia-based company lost 238,000 basic video customers as it contends with rival phone and satellite companies as well as a weak U.S. economy.

Collins Stewart had forecast losses of 225,000 video customers.

Investors have been concerned pay-TV operators would get hurt by cheaper nimbler Web-based video services like Netflix Inc and even Hulu in which Comcast owns a stake. Time Warner Cable, the number 2 cable operator last week said it lost 128,000 video customers during the quarter.

(Comcast's) numbers were pretty good though basic video losses remains a concern for investors, Collins Stewart analyst Thomas Eagan said. We're close to the broader pay-TV market being flat to down this quarter due to seasonality and the economy.

Excluding one-time costs, second quarter profit was 42 cents ahead of the average analyst forecast of 41 cents, according to Thomson Reuters I/B/E/S.

Comcast completed its acquisition of a controlling stake in NBC Universal earlier this year. Including NBC Universal's results in both 2010 and 2011, Comcast's revenue rose 9.4 percent to $14.33 billion on a pro-forma basis.

NBC Universal's total revenue rose 17 percent to $5.18 billion driven by a strong performance across its cable, broadcast, movies and theme parks business.

Standouts for the quarter included a rise of 10 percent in advertising sales at its cable networks, which includes Bravo, MSNBC and USA Network.

The turnaround at its NBC broadcast TV business continued with overall revenue rising 18.5 percent -- partly driven by a 7 percent rise in advertising revenue.

Universal Studios also had a strong quarter thanks to box office hits including 'Fast Five' and 'Bridesmaids' which was offset by industry wide drop off in DVD sales and lower content licensing revenue.

(Reporting by Yinka Adegoke; Editing by Derek Caney)