Semi-blanknut 41CX


I recently came across a rather strange HP beastie. It is an HP41CX blanknut, but the upper rows of keycaps have the shot molded legends. These keycaps on a standard blanknut do not have shot molded legends.

The keyboard background is a standard blanknut unlabeled black. The front label is gold and just says "Hewlett Packard" without any "41CX".

This unit came with an HP-IL interface to a custom data acquisition box.


Sounds like a special made for a company.

Can you post photos?



I once saw a 41 that was purported to be a blanknut. However, under close inspection, it looked like the key legends had been buffed off.

The blank keyboard background had the tabs (that fit in slots) that you see on a normal blank overlay.

So, it looked like someone just faked a blanknut. Pulled the old legend off and applied a blank template (forgot to remove the tabs and buffed off the key legends.

Is there any way to tell a blanknut other than the blank background and missing labels on the keys?


This one is definitely the real thing. Proper blanknut background and the front label is correct for a blanknut. No signs of buffing, etc. Also it came from a very reliable source (a university junk pile... for free). I won't have any way to do digital photos for a while.

I suspect that it was either a custom-custom ordered unit or HP accidentally picked up a normal keyboard and applied the blanknut labels to it when sombody ordered Option 001.

I have a couple of HP25C units that had similar manufacturing errors. One has a 25C front label without the "Continuous Memory" script on the keyboard. Another has the "Continuous Memory" script but a normal HP25 front label. Both came from sources (and at prices) that had no motive to mess with faking.

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