View Full Version : Trying to figure out how to date the chips in my DIY Apple II

December 3rd, 2013, 08:54 PM
Hey guys,

I'm trying to get an idea as to how long ago this custom Apple II was built. I thought a clue might be garnered from the chips themselves. IIRC and via google, I believe most chips have a 4 digit date code, with the first two digits being the year and then the other two being the week of production?

Here's some examples:

SFC 451LSJM 54LS51 7818 (18th week of 1978?)

F 54LS174DM 8146 (46th week of 1981?)

ITT 7904 4116 2J (4th week of 1979?)

SN54LS161J 7652L (last week of 1976?)

NE558N 8130 (30th week of 1980?)

If correct, it looks like the majority of chips date from the late 70s, with a few up into the early 80s. Those 'flash' EEPROMs in use for what I presume is Integer or Applesoft Basic are MBM2732A-35 8222 C74, which I assume means 22nd week of 1982.