The Museum of HP Calculators does not assume any responsibility and shall have no liability, consequential or otherwise, of any kind arising from the use of this information. General tips Calculators are sensitive electronic devices. Observe static precautions when opening them. Dangerous voltages may be present in some models long after they have been turned off. Don't overtighten screws on reassembly - especially on plastic models.
Card readers have tiny parts which can disappear on a typical floor.
On card reader models, remove two screws from under small caps near the AC adaptor socket. On non-card reader models, remove two screws from inside the battery compartment. A hair dryer might help to soften the adhesive. Additional screws hold the spine to the front case. When the spine is removed, all of the keys and switches will be freed so be careful.