HP-33c rattles


Hi there,

I just bought a 33c at eBay (don't ask me how much I paid ;-) which is in very good condition. It almost looks brand new. After I replaced the batteries, which ran out a bit, it works fine. The only problem for me: It makes a ratteling sound similary to a match box when I shake it. The sound seems to come from the keys (not from loose parts). I have also a 32e (which looks almost identical) that doesn't make that sound.

Any idea what I can do? Please don't tell me not to shake it ;-)
Is there a way to fix the keyboard? I don't want to open the case unless I'm shure that a can do something useful...

Kind regards
Bert Oberholz


There is a foam pad that lies under the keys. It may be missing for some reason on your machine.


In my experience all the Spice series calculator keyboards rattle. Some more than others, but they all rattle.


Do old-construction machines rattle more than the newer ones (with a real PCB)? Testing 3 machines here suggests that the 2 older ones (a 33C and 32E) rattle a bit more than the newer one (a 32E again, but with missing parts).
That's nowhere near a representative sample. of course.
As regards opening up the machine, the Spice series is one you can open without having to peal off labels, etc, so you can do it without damaging the appearance of the machine. If it rattles excessively then you might want to take off the bottom case to see if there's anything loose inside.
Openning Spice machines has been covered here many times, but here you are again. Remove the battery cover and battery pack; Undo the 2 screws in the battery compartment; Place your thumbs in the battery compartment, your fingers on the front edge of the top case, and squeeze (the idea is to slide the bottom case towards the front (non-display end) of the machine);
When you hear a click, the cases have separated, so carefully lift off the bottom case, ensuring it doesn't damage the battery contacts.


Hi Erik, David, Tony,

thanks for the information.


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