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Opening an HP-21



#4

Does anyone know the "proper" way to crack open an HP-21? It looks like the only possible way to get in is by removing the top cover. How should I go about this? How did HP put these things together in the first place, glue? Thanks for your help.


#5

Jonathan,

The screws are located under the feet.

#6

If I remember right, the rubber feet near the display end of the calculator are inserted into rectangular recesses in the bottom case. These may be slid out, and a cross-head screw is underneath each. After taking out the two screws, the face comes away from the case at the display end. It is retained at the other end by a tab inserted into a recess inside the case, and comes apart easily. (Again, if I remember correctly!)

Good luck.


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