Dating rca vacuum tubes
This is the second in our on-going What It’s Worth series that keeps you up to date on what’s hot in Antique Technology. Again, dig through your attic and basement and let us know if you find something you need reviewed.If some of you have home electronic workshops like me or a section of your warehouse where no one's been in years, you probably have older electronic components stashed away on shelves or in boxes you haven't seen in quite some time.If you are looking for a hard to find vacuum tube, we can nearly guarantee that it is in our inventory and available today! I have a bunch of Computer grade Sylvania 6350's made for the Buroughs Corp. I've searched the Web for a key to Sylvania date codes, but no luck. I am sure when Sylvania was in business they could have used internal paperwork to trace a production lot to a specific line and date, but there is no translation scheme to get years and dates out of them.Amperex (USA) 111 Bendix 125 Du Mont 158 Eimac (Eitel-Mc Cullough, Inc) 162 Electronic Tube Corp 169 General Electric Co (USA) 188 Hytron (CBS-Hytron) 210 Machlett 231 RCA (Radio Corp of America) 274 Raytheon 280 Superior Tube Co 310 Sylvania (Hygrade Sylvania Corp) 312 Tung-Sol 322 United Electronics 323 Western Electric 336 Westinghouse 337 Zenith Radio Corp (CRT's) 343 North American Philips Corp 423 Taylor (aka Cetron-Taylor) 713 Lewis & Kaufman 738 National Electronics (also Cetron) 749 Penta Laboratories 771 Vacuum Tube Products 781 Varian Associates 809 Litton Industries 879 Electrons, Inc 935 USA (RETMA) system First number: filament voltage 0 Cold cathode (e.g. 1 0.1 - 2.0 2 2.1 - 2.9 3 3.0 - 3.9 n n.0 - n.9 Letter or letters: sequence code One or two letters to indicate the sequence code. 12AY7: Filament rating is between 12.0 - 12.9V, AY=sequence code, 7 elements. The "hole" in the top mica identifies these USA made tubes from the TUNG-SOL factory in Newark, New Jersey, USA in the 1950's.
We do exactly as we promise and we stand behind our customers 100%We stock radio and vacuum tubes for every application from all major manufacturers including RCA, GE, Sylvania, Raytheon, Tungsol, and Amperex. Other systems prefix the number with the letters JHS or JAN. Confusingly, the British also had two entirely different VT nomenclatures, one used by the Royal Air Force and the other used by the General Post Office, responsible for post and telecommunications at the time, where it may have stood for Valve, Telephone; none of these schemes corresponded in any way with each other. One system prefixes a three-digit number with the letters "VT", presumably meaning "Vacuum Tube". Like the British military system, these have many direct equivalents in the civilian types.Note that U - Z generally (but not always) as the only character, or last character, are used for rectifiers Final number: Element count The number of elements in the tube, the filament counting as 1. AND UNITED-ELECTRONICS WAS OUT OF BUSINESS IN 1988!For example, the 6SN7 has two cathodes, two grids, two plates, and a filament. SO 88-37 WAS UNITED-ELECTRONICS INTERNAL NUMBERING SYSTEM AND DID NOT SIGNIFY ANY MANUFACTURING DATE.