For its high-definition broadcasts, the network will use a 720p transmission, the same as that used by ABC.

Many people may not be ready to buy a new television when digital high-definition broadcasts begin in the nation's 10 largest cities this fall.

Most of the new digital televisions are being used to watch high-definition over-the-air broadcasts, he said.

In Japan, where a form of high-definition broadcasts began late last year, the television sets have sold for about $30,000.

The Blu-ray companies, by contrast, are betting that consumers will want machines that can record high-definition broadcasts.

From 28 September 2009 and onwards, the channel used standard high-definition broadcast.

This is also the medium for high-definition broadcasts around the world and 1080p is used for Blu-ray movies.

The increase in high-definition broadcast and cable programming has prompted more consumers to buy high-definition television sets.

Mr. Baker gave him instructions on how to tune in a high-definition broadcast over the air.

Japan is already planning to begin high-definition broadcasts next year, and Europe is working on its own system.