Your dating tube
Therefore, batch 0 was 0, batch 1 was 1, batch 10 was A, and so forth until the end of the list.
), and this You Tube date has been our favorite one so far!
It follows this convention before 1956: Where TT stands for the one, two, or three symbol tube type code, C is the change code, F is the factory and/or country code, and M is the month of manufacture.
On the bottom of octal base tubes the code is usually FM/TTC.
It also contains a page or so of the factory codes as well. You can either view or download it by clicking on this link (left click to view, right click and select "save target as" or "save link as" to download): Download or view the tube type code list.
Please let me know if you have any questions on using this page.
I have scanned a printed list of the most comprehensive factory/country codes, as they contain a great many symbols not found on the standard USA computer keyboard.