[Doc Ewen looks into the horn antenna, 1950]
Image courtesy of Doc Ewen


Harvard Cyclotron: 1948-1951

Detection of HI Line: 1951

Harvard 24ft and 60ft and NRAO founding: 1952-1956

1950s and 1960s: Two Roads that Crossed

Microwave & Millimeter Wave Applications in the 1970s and 1980s

Mm Wave Radiometry in the 1990s

May 2001 visit to NRAO Green Bank



[Doc Ewen and horn antenna, 2001]
Image courtesy of Doc Ewen

Doc Ewen: The Horn, HI, and Other Events in US Radio Astronomy

by Doc Ewen, © 2003

Slide 20: Detecting the Interstellar Hydrogen Line, 1951

[Mixer connected to horn]

The mixer, in the foreground, is connected to the throat of the horn via a slotted line. [Photo courtesy of Doc Ewen]

Slide 21
Modified on Tuesday, 28-Sep-2004 15:34:15 EDT by Ellen Bouton