Not shure how to identify the year I looked in the oracle and cannot find anything. Need help

Hi,
Zenith often inks a number on the back of the chassis, say for the 10S153, the chassis has an inked stamp of 1004, but the actual model number breaks down to a series of number(s), letter, Numbers. The first number(s) indicate the number of tubes.

So if you have several numbers, look for the one that has a letter, and if the digit(s) ahead of that number is equal to the number of tubes, you found it.

Sometimes the model number is embossed into the bottom of the chassis board (on consoles- This is just the board that the chassis bolts to.), and once in a while on the bottom of the radio itself.

:Not shure how to identify the year I looked in the oracle and cannot find anything. Need help
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