Atwater Kent Manufacturing Company, Philadelphia Pennsylvania

Date added: March 21, 2016 Categories: Pennsylvania Industrial
1996 View of the South Plant from the Roof of the North Plant

Atwater Kent was the largest producer of radios in the world in the late 1920s. Atwater Kent was an important twentieth-century inventor and manufacturer of radios and electrical components for automobiles.

The Atwater Kent Manufacturing Company factory on Wissahickon Avenue in northwest Philadelphia was built by Arthur Atwater Kent between 1923 and 1929 for the purpose of manufacturing radios and associated components. The factory consisted of two main facilities known as the South and North plants, which together covered more than 34 acres. The South Plant was completed in 1923, and was expanded in 1925. The South Plant was later connected by an enclosed pedestrian bridge to the North Plant during construction of the latter in 1928 and 1929.

The Atwater Kent Manufacturing Company was incorporated in 1919 by Arthur Atwater Kent. The company was an outgrowth of two previous unincorporated companies formed by Kent: the Atwater Kent Manufacturing Works, a sole proprietorship founded in Philadelphia in 1902, and its predecessor, the Kent Electric Manufacturing Company, founded in Worcester, Massachusetts, in 1895. Both of these earlier firms engaged in the manufacture of small electrical items, including motors, fans, meters, and intercommunicating telephones.

Atwater Kent Manufacturing Company, Philadelphia Pennsylvania 1927 Atwater Kent Radio Ad
1927 Atwater Kent Radio Ad

Kent was born in Burlington, Vermont, in 1873. He attended Worcester Polytechnic Institute, but left there in 1895 after two years of study to form the Kent Electric Manufacturing Company. The company produced motors and fans which Kent marketed himself through magazine advertising and sales trips through the Northeast. During a trip to Philadelphia, Kent became excited about the business prospects in that city and in 1902 relocated there, opening the Atwater Kent Manufacturing Works in a loft at 6th and Arch streets.

Kent was a prolific inventor who obtained 93 patents over his career. He manufactured many of his inventions himself, constantly adding to his product line. He diversified into electrical components for automobiles, and achieved a huge success in 1905 with his invention of an improved engine ignition system he called the Unisparker. His device produced a single quick hot spark instead of the ordinary stream of sparks, and combined ignition points, condenser, centrifugal advance mechanism, and distributor in one unit. The Unisparker was immediately adopted by a dozen automobile manufacturers, and the general concept was in use in automobiles until the recent development of fully electronic systems. The Franklin Institute of Philadelphia awarded Kent the John Scott Medal for inventive achievement in 1914.

By 1911, Kent's company had grown to 125 employees, and moved to larger manufacturing facilities on Stenton Avenue in Philadelphia. Automobile starters and lighting systems were added to the line, and during World War I, Kent received government contracts for the production of fuse-setters, clinometers, and optical gun sights. With the economic slowdown following the war, and because more auto manufacturers were installing their own ignition systems, business began to slump. Kent incorporated in 1919, and began to look for other electrical products to manufacture.

The public was fascinated with radios, and by 1921, Kent was moving rapidly into the burgeoning new field. He possessed the necessary specialized tooling and equipment for working with Bakelite, an extremely tough synthetic insulator used in electrical equipment. The company began with the manufacture of radio components and quickly moved into the manufacture of complete radios. The fall and winter was the radio "season," and each year there was tremendous competition among the hundreds of manufacturers to bring forth new and improved models. Kent brought numerous firsts to the radio marketplace, including radios operating on alternating current. He popularized one-dial tuning and the sheet metal cabinet, which further reduced production costs and expanded the low-end market.

While maintaining high quality, he continually drove the price of radios down through largescale and efficient production methods. In 1923, Kent began construction of a new manufacturing facility in northwest Philadelphia. Kent hired the architectural engineering firm The Ballinger Company of Philadelphia to design the facility, utilizing the "Super-Span Saw-Tooth" roof trusses patented by Walter Francis Ballinger and Clifford H. Shivers.


Kent believed strongly in advertising, and mounted extensive campaigns on radio and in magazines and newspapers which kept him in position as the market leader. In 1925, Kent sponsored the Atwater Kent Hour radio program, which featured the leading musical talents of the day and quickly became one of the most popular radio programs. By 1927, Kent was spending over three million dollars a year on printed advertising and seven thousand dollars a week on his radio program. In that same year, the South Plant produced over one million radios, the greatest production of any radio manufacturer in the world. In 1928, Kent expanded the facility with the construction of the North Plant, again hiring The Ballinger Company and employing their special roof system. It was at that time that the pedestrian bridge was built over Abbottsford Avenue, connecting the North and South plants. The bridge was later demolished with the construction of Route 1. With the completion of the North Plant, production rose to over 6,000 radios per day, totaling nearly 2.2 million units per year and employing approximately 12,000 workers.

Kent's success in the manufacture of radios was not primarily due to his inventive genius, as was the case with his earlier electrical devices. All of the radio manufacturers relied on patented technology controlled and licensed by the Radio Corporation of America (RCA). Kent illegally "borrowed" proprietary technology, assembled it in a more attractive product at a lower price, flooded the market with advertising, and captured millions of dollars in sales before the legal system could catch up. In 1927, Kent lost two patent infringement suits brought by RCA and the Hazeltine Corporation.

The meteoric rise of the company was followed by an equally rapid fall during the years of the Depression. Along with the economic downturn came overpowering competition from other radio manufacturers such as Philco, and increasing demands from labor unions. Kent was forced to cut his workforce, and in 1931, he set up a private relief fund to assist 3,500 of his former employees who could not find other work. By 1936, Kent's labor force had been cut to 800 employees, and Kent decided to get out of the business entirely while his personal fortune was still intact. In that year, Kent dissolved the corporation, auctioned off the equipment, and permanently closed his sprawling plant. Over the next two years, Kent restored the Betsy Ross house in Philadelphia, and also restored the old Franklin Institute, which he donated to the city for use as a museum of Philadelphia history. In 1938, the city renamed it the Atwater Kent Museum. With a fortune estimated to be in the millions, Kent retired to Bel Air, California, where he pursued social and philanthropic activities until his death in 1949.

Kent sold the North Plant on August 1, 1941, to the U.S. Signal Corps for $2 million, after the government had filed condemnation proceedings in Federal District Court one week earlier. According to a government press release, the 740,000-square-foot building and the land represented an investment of $3.5 million. The Signal Corps Depot officially celebrated its opening on November 15, 1941, with ceremonies attended by Philadelphia Mayor Bernard Samuels and U.S. Senator Hugh Scott. In 1949, ownership of the building was transferred to the newly formed General Services Administration (GSA). The GSA completed the conversion of the building from manufacturing space to office space and records storage, a use which continues today. The building's first tenant under the GSA was the Veterans Administration in 1949, joined by the National Archives in the 1950s and the U.S. Treasury in the 1960s.