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peter · (This post was last modified: 06-05-2016 07:50 AM by peter.)

My first post!

After a quick browse on the forums, I could not find similar information and thought to post.

I recently purchased 4 HP 12C's, 2 made in 1984, 1 made in 1987, 1 made in 1988.

Looking more closely, I noticed that HP 12C's made in 1984 or before do not have the 871B logo, nor the "Complies with the limits for a Class B...." text.
This can be useful to note when shopping auction sites for pre 1985 calculators. An image is attached below as an example.

Serial # 2747A above, # 2434A below

On the 1987 as well as the two 1984 calculators, it looks as if some of the keys were (re)molded from an 11C or a 15C. Under a certain light you can see very faintly that some of the keys have different inscriptions - The images attached below attempt to get the right lighting to show the original e x below the i key (1987 calc).

Was it possible some of the keys were re-molded, or perhaps the manufacturing process shares the parts between calculators that might then leave an imprint?

Thanks!
Peter