Sylvania (NA) Lamp Date Calculator
This calculator gives up to 4 possible options of what that date might be, depending on which decade the lamp was made in- you'll have to decide which one applies most closely to the lamp in question. All this does, is remove the need for you to do the maths of which month code is which date.
There should be 3 digits on the side of the lamp cap preceded by the letters 'SR', or for older lamps pre 1981, 2 or 3 digits with the etch.
There is currently some discussion as to when this code cycle started, 1961 or 1960. This calculator assumes 1961, hence the lamp could possibly be 1 year older than the result.
It covers lamps made between then, and the early 1990s. I have no info as to whether this code cycle covers 1950-1960, so I've not included that decade.
Younger lamps than that will have a different type of code, try the Osram/Sylvania calculator for that.
This was made possible following posts to Streetlighting UK by Colin Grimes, May 2009.
There should be 3 digits on the side of the lamp cap preceded by the letters 'SR', or for older lamps pre 1981, 2 or 3 digits with the etch.
There is currently some discussion as to when this code cycle started, 1961 or 1960. This calculator assumes 1961, hence the lamp could possibly be 1 year older than the result.
It covers lamps made between then, and the early 1990s. I have no info as to whether this code cycle covers 1950-1960, so I've not included that decade.
Younger lamps than that will have a different type of code, try the Osram/Sylvania calculator for that.
This was made possible following posts to Streetlighting UK by Colin Grimes, May 2009.
Enter 2 or 3 digit date code from lamp
Don't enter the 'SR' if it precedes the numbers.