Date electronic equipment by the codes found on the components
This is handy when trying to find the date of manufacture for American electronic instruments such as vintage synths, guitars, amps and stomp boxes. Pots, speakers and many other components made in the US often have an EIA code on them which will identify the manufacturer and the date of manufacture. Gather together all the date codes from the those components and this tool will tell you that the unit was made some time after the latest date (not including any replacements of course).
It should be noted that large manufacturers often stocked up on components in large batches so the unit may be made a year or more after some of its components. For pots this code is 6 or 7 digits. 6 digit codes may not be able to be narrowed down to a specific decade as only the last year digit was included into the number, some codes may return more than one option. The codes may contain spaces or dashes, if so please include them. Pots made by IRC use their own format which is also supported, this will start with 615 and will have 2 spaces in it, you must include those spaces. I have also included some Gibson guitar specific codes. If dating a Fender guitar it should be noted that in 1966 Fender bought a huge stock of pots which were used right up until 1971 so it is possible for a 1971 guitar to contain 1966 pots.
This should now be working for all speaker manufacturers, they can have codes of between 5 and 8 digits possibly containing spaces or dashes