I turned to the Internet to do some more networking which resulted in a major turn of events as I met two individuals who have become instrumental partners in this project: Greg Huntington and Devin Riebe.Greg is a long time Fender collector who is very knowledgeable not only in the details, but in the circuitry as well.His particular area of expertise is in Fender amps made from about 1960 through 1967.Devin runs Doc's Music in Springfield, Missouri and his interest lies in the woodie and tweed Fender amps made from 1946 through 1960.In order to date a Fender amp or provide the value, you need to know one of the below: * The 2 letter date code rubber stamped on the Tube Chart, or * The 2 letter date code on the QA Sticker, or * The Transformer Number that starts with “606-XX-XX”, with the 3 or 4 Xs being the unknown numbers that need to be provided by the owner of the amplifier asking the question.: The transformer number tells you when the transformer was made and not necessarily the date the amplifier left the Fender Factory, the “2 Letter” date code on the Tube Chart or QA Sticker actually tells you that and that makes it the most accurate option for dating the month and year it was made.... For most purposes, the vacuum tube has been replaced by the much smaller and less expensive transistor, either as a discrete device or in an integrated circuit. and Canadian English) or (thermionic) valve (outside North America) is a device generally used to amplify, or otherwise modify, a signal by controlling the movement of electrons in an evacuated space.
For more information, please visit this site: Fender Support kcbuck So... They are not of a concern with dating as only the 2 letter date codes on whichever chart or sticker and the transformer number comes into play for that....There are other ways but the above is a more accurate method.Vacuum tubes, or thermionic valves, are arrangements of electrodes in a vacuum within an insulating, temperature-resistant envelope.Although the envelope was classically glass, power tubes often use ceramic and metal.