Dating a Model F/XT with no date code?

[modelf]

This was an eBay purchase. I was intrigued by the multiple QA labels. However, nowhere on this keyboard is there a date code. I'm wondering if it's possible to date this to a particular year... based on the information that is there on some of the internal labels and stamps?

Here's the keyboard, and a few interior pics:











Thank you for your help!

[Nikki2981]

Both of mine have at least something resembling date markings on the inside of the case itself, but nothing on any of the components or the PCBs.

This one is on the back plate

...And this one is on the plastic shell


I imagine you've already looked there and not found anything, so if nothing of the sort is there then I'll leave this to someone smarter than me to figure out...

[modelf]

Thanks for the reply! I have a few other F/XTs. Each has either a date code on the large QA label on the backplate, or a date stamp on one of the case halves (or, sometimes, both). This one, however, doesn't have any of the above. It's a total mystery. (There is a stamp on the inner top case, but it doesn't appear to correspond to a date.)

[Ellipse]

The PCB in your photo is labeled 8210 indicating the 10th week of 1982.

[modelf]

Ah so obvious, and yet not... if you don't know what to look for. Thank you so much Ellipse!