Harry Houck, Edwin Armstrong and the Superheterodyne Receiver

Superheterodyne receiver with U.S. Navy amplifiers at Sea Gate Station.
Pennsylvania State Archives, MG-424

Harry Houck (1897–1989), a pioneer of radio technology, was born and raised in New Cumberland, Pennsylvania. At the age of 14, he built his first ham radio rig and began transmitting and receiving messages. He graduated from Harrisburg Technical High School in 1916 and then joined the U.S. Army shortly after the United States entered World War I on April 6, 1917.

In February 1918 Sergeant Houck began serving under Captain (later Major) Edwin Armstrong (1890–1954) in the Army Signal Corps. They worked together on their mutual interest in radios while in the Army and became lifelong friends.

Diagram of the superheterodyne system.
Pennsylvania State Archives, MG-424

Houck collaborated with Armstrong in the development of the superheterodyne radio receiver, essential to maximal performance in sensitivity, the ability to receive information from a weak signal, and selectivity, the ability to receive only the signal that is tuned in while blocking others that are close in frequency. This was a major technological breakthrough in the history of radio (although others had discovered the principle around the same time, with French engineer Lucien Lévy filing his patent shortly ahead of Armstrong). Virtually all modern radios still use the superheterodyne principle.

Armstrong and Houck’s work in France ended suddenly with the Armistice on November 11, 1918; however, the advent of commercial radio broadcasting in the 1920s brought a new significance to the superheterodyne. Therefore, in 1922 Armstrong and Houck constructed a receiver set designed for maximum sensitivity and selectivity. This receiver was superior to any others available at the time, but the expense of construction and maintenance was cost prohibitive. Armstrong and Houck then began designing the second harmonic superheterodyne, which reduced the number of tubes required from nine to six and was practical for home radio reception. This superheterodyne was an integral part of the first receiver to be placed into mass commercial production.

Harry Houck in his later years.
Pennsylvania State Archives, MG-424

While Armstrong went on to develop FM radio and other innovations, Houck began work as chief consultant and chief engineer at the Dublier Condenser and Radio Co. from 1923 to 1931 and then was a consultant for Federal Telephone & Telegraph and Micamold Radio Corp. through the 1930s. Later, in 1940, he became the president of Measurements Corp. in Boonton, New Jersey, which produced high accuracy instruments for measurements in the radio field. In 1953 Measurements was acquired by Thomas A. Edison Inc., and in 1958 another merger created McGraw-Edison Co., with Houck in both cases serving as vice president and general manager. He retired in 1967. The list of U.S. patents he held was close to 90.

Houck was also an active member of the American Institute of Electrical Engineers, the Institute of Radio Engineers, the Engineers Club, and the Radio Club of America. His exceptional influences on the development of radio were recognized in 1941 when he was awarded the Edwin Armstrong Medal by the Radio Club of America.

The Harry Houck Collection (Manuscript Group 424) resides in the Pennsylvania State Archives. It consists primarily of photographs and manuscripts related to early radio equipment and pioneers in the field. A large portion of the collection is devoted to Edwin Armstrong.

Richard C. Saylor is an archivist for the Pennsylvania State Archives and author of the award-winning book Soldiers to Governors and numerous articles on military, political and sports history.