HP9100 Desktop Calculator article and photographs
HP25A and HP25C Internal Photographs
HP35 Internal Photographs
Article about HP55 Technical Information and Internal Construction
Article about HP67 Technical Information and Internal Construction
HP41C Family Internal Photographs - Card Reader photos
HP46 Internal Photographs
HP97 Internal Photographs
HP9830 Internal Photographs
Photo of HP 32S - 50th Anniversary Limited Edition model calculator and soft case with logo and inscription.
Photo of interesting ROM drawer for 9835 calculator, with 98332A I/O ROMs installed in the left one and 98331B Mass Storage ROMs installed in the right one. Numbered ROMs with unknown functions shown underneath.
Photo of HP9821 desktop calculator (similar to HP9820 but with tape drive instead of card reader). Photo courtesy Dermot Rush
Article archive from HP KEY NOTES newsletter
Click here to go directly to the Desktop Calculator Gallery
Click here to go directly to the Pocket Calculator Gallery