57T227

Pages 762 and 763 of the Fall 1929 Sears Roebuck catalog lists Silvertone tubes for the first time, with a totally new catalog number, for example 57T227 = UY227. Research has not yet provided a manufacturer of these tubes or a location of a factory and Tyne's "Saga of the Vacuum Tube" page 362 states: "No information available" for Silvertone. It is presumed that these tubes were made by the Sonatron Tube Company and it is also known that Sonatron acquired three smaller companies before they themselves were acquired by National Union in September 1929 (Tyne page 359). Silvertone tubes continued to be available for some years and tube boxes with both Sears Roebuck and Silvwetone printed on them are relatively common in the US.Sears Roebuck Archives state that the company "ended its association" with Sivertone (radios and or tubes is uncertain) in 1972.