Y227

Common type USA tube/semicond. Air King - tubes Apollo Radio Tube Company; New York City, NY, Irvington, NJ Arrow Tube Company; Springfield, MA Champion Radio Works; Danvers, Massachusetts Crescent (tubes); (where?) Croydon (where?) Duovac Radio Tube Corp.; Brooklyn, NY Empire-Tron (tube brand) Everite Tube Co.; Providence, RI Franklin Radio Company; Chicago, IL Gold Seal Electrical Co., Inc.; New York Hygrade Lamp Co. (Neptron); Salem, Massachusetts Hylon (tubes), brand Hytron; Salem (MA) JRC, Johnsonburg Radio Corporation; Johnsonburg, PA Knight (tubes), brand Midwest Radio Co., The, (Miraco); Cincinnati, OH National Tube Mfg. Co. (brand), National Products - see also Continental Corp; Chicago, IL Neonlite Corp. of America; (where ?) Pioneer Engineering Laboratories; Jersey City, NJ Selectron (tube brand) Sonatron Tube Company; Chicago and New York The Talker (tube brand) Voxola Manufacturing Co.; New York City, NY