Jan 19 (Reuters) - Wall Street’s main indexes opened higher on Tuesday after upbeat earnings from big U.S. banks and Halliburton, while investors awaited a speech from U.S. Treasury Secretary nominee Janet Yellen that is expected to advocate hefty fiscal spending. The Dow Jones Industrial Average rose 73.2 points, or 0.24%, at the open to 30887.42. The S&P 500 rose 13.6 points, or 0.36%, at the open to 3781.88, while the Nasdaq Composite rose 134.2 points, or 1.03%, to 13132.728 at the opening bell. (Reporting by Devik Jain in Bengaluru; Editing by Maju Samuel)