Serial Number: There is no information readily available for dating Fender amps by serial number but there are people working on it. Circuit Code: In 1963 Fender stoped using model numbers to identify schematics and began using the model name and an assigned circuit number.
These circuit numbers which are located on the tube chart can be usefull for getting a rough date on an amp.
Fender installed casters on some larger amps and cabs beginning in 72.
Oddlings – Yet another printing error has surfaced, this time from the FEI (pre-CBS) days.
The next one or two numbers are the month where January is 1 and December is 12. Example: AB763 = second revision, July, 1963 AA1070 = First revision, October, 1970 Misc Dating Info: Silver face amps with the aluminum trimmed grilles are from 67 or 69.
The fist Master volume controls were first installed in 72.
For instance, he confirmed our assumption that the amp chassis were put into stock after being stamped with serial numbers and that the chassis were pulled from the stock bins randomly (just as with Fender guitar neck plates).