Vintage DOD Effects Pedals Pot Codes – Dates

Pot
“Pot” is short for a potentiometer. A potentiometer is a manually adjustable resistor. A potentiometer is used to control the potential difference, or voltage, across a circuit.

Codes
There are two sets of numbers on the backside of the pot; the first set is the value (output). For example: 100k, etc. And the second sets of numbers are the manufacturers code, and the date of manufacture. For example: 1378111.

Dates
DOD’s pots of 70s and some of 80s era were manufactured by CTS Corporation. There are seven digits on the pot. The first three digits are CTS’s manufacturing code number: 137. The next four digits is the date: 8042. For example 1378042: 137 means it was made by CTS, and 8042 means it was made in 1980 in the 42nd week. (This is the date that the Pot was made NOT the effects unit.)
Back then it may have taken anywhere from the start of the production date to several weeks, or even more, for the pot to reach the pedals manufacturer. And it may also have taken time for the pots to be installed in to the effect/s. Ultimately, the effect was made much after the oldest date engraved on the pots.

Examples (Important)

1. If the pot code is 1378042, this would be a 1981 pedal, as the 42nd week would mean the pot was made in the middle of November of 1980 and took time to deliver. Therefore the effect would have most likely been made in 1981.

2. If the pot code is 1378111, this would be a 1981 pedal, as the 11th week would mean the pot was made in the end of March of 1980 and took time to deliver. Therefore the effect would have most likely been made somewhere in middle of 1981.

The same could be applied to other effects manufacturers of that period. For example: MXR.