On January 15, 1907, Lee DeForest received U.S. Patent No. 841386 for Wireless Telegraphy and 841287 for a Device for Amplifuing Feeble Electrical Currents:

The vacuum tube amplifier was a critical component of early radios and televisions, until transistors replaced them. For his pioneering work, de Forest has been credited as the “Father of Radio”, an appellation he adopted as the title of his 1950 autobiography.