Narrator (voice)

Jason Robards

Acting

Self - Radio Announcer

Red Barber

Acting

Self - Historian

Erik Barnouw

Writing

Self - Biographer of David Sarnoff

Ken Bilby

Acting

Self - Writer

Norman Corwin

Writing

Self - Historian

Susan Douglas

Acting

Self - Engineer

Frank Günther

Acting

Self - Niece of Edwin H. Armstrong

Jeanne Hammond

Acting

Self - Engineer

Loren Jones

Acting

Self - Writer

Garrison Keillor

Acting

Self - Radio Broadcaster

Helen Kelley

Acting

Self - Engineer

Robert Morris

Acting

Self - Friend of Edwin H. Armstrong

Dana Raymond

Acting

Self - Engineer

Gertrude Tyne

Acting

Self - Predicts Demise of Radio (archive footage)

Fred Allen

Acting

Self - Sings (archive sound)

Gene Autry

Acting

Hamlet (archive sound)

John Barrymore

Acting

Self - Finest Hour Speech (archive sound)

Winston Churchill

Acting

Self - Prepares for Amos 'n' Andy Broadcast (archive footage)

Charles J. Correll

Acting

Self - Objects to Quality of Radio Programming (archive footage)

Lee De Forest

Directing

Self - Host of 'This Is Your Life' (archive footage)

Ralph Edwards

Acting

Self - Announces Landing in Normandy (archive footage)

Dwight D. Eisenhower

Acting

Self (with Lee De Forest) (archive footage)

Eugenia Farrar

Acting

Self - Prepares for Amos 'n' Andy Broadcast (archive footage)

Freeman F. Gosden

Acting

Self - Visits Sarnoff at RCA (archive footage)

Guglielmo Marconi

Acting

Self - with Lee De Forest (archive footage)

Marie Mosquini

Acting

Self - Eulogizes Sarnoff (archive footage)

Nelson Rockefeller

Acting

Self - Makes Broadcast About Banking Reform (archive footage)

Franklin D. Roosevelt

Acting

Self - with Marconi at RCA (archive footage)

David Sarnoff

Acting

Self - Serenades Sarnoff (archive footage)

Frank Sinatra

Acting

Self - Conducts NBC Symphony (archive footage)

Arturo Toscanini

Acting

Self - Announces Bombing of Hiroshima (archive sound)

Harry S. Truman

Acting

Self - This is Your Life Announcer (archive footage)

Bob Warren

Acting

Self - Professor in War of the Worlds Broadcast (archive sound)

Orson Welles

Directing