A partially-disassembled HP-29C calculator.

1977 era Hewlett-Packard 29C calculator in Kanata, Ontario, February 12, 2016. Photo by Garth Gullekson

Way back in the fall of 1977, I began my studies in Electrical Engineering at the University of Waterloo. I decided to upgrade my calculator to the new HP-29C, a second-generation HP calculator with continuous memory. Earlier calculators in the first generation of HP calculators, such as the HP-35 and HP-45, lost the contents of their memories when powered off. However, the HP-29C was programmable, and a program was somewhat tedious to enter, so you were now losing programs in addition to the register locations. So, the ability to retain the memory when the calculator was turned off was a big deal at the time.

I used my HP-29C throughout my university days. Eventually, it was replaced by an HP-12C financial calculator and an HP-15C scientific calculator, both of which are within arm’s reach as I sit here typing at my desk. These two new calculators relegated the HP-29C to the basement in the box in which it arrived along with manuals, a spare battery pack, and more. Until a few days ago.

An HP-29C calculator held by a hand.

1977 era Hewlett-Packard 29C calculator in Kanata, Ontario, February 12, 2016. Photo by Garth Gullekson

My close friend, Garth Gullekson (Facebook), embarked on a mission to greatly reduce the clutter in his basement. Like an excavation for relics, he uncovered some gems from his past as well as stuff easily recycled or discarded. You can read more about this adventure on his Facebook page. Among the treasures rediscovered was an old Texas Instruments SR-50 calculator from his early university days. Although barely functional, he restored it to working order.

With news of Garth’s resuscitation of his old SR-50 making the rounds of his friends, other older calculators surfaced and Garth has now repaired several, including my old HP-29C. We thought the calculator wasn’t going to work at all because the display would only flash intermittently with power applied to it. However, after disassembly, cleaning, and reassembly, Garth was able to bring it back to life. I still have the original box, manuals, case, charger, spare battery pack, and even a pamphlet about the calculator.

This calculator has been with me since I started Engineering at university and it was with me when I retired, thereby spanning my entire engineering career.

Below are the pictures that Garth took of the fully functional calculator along with the case, charger, spare battery pack, quick reference guide, manuals, brochure, and original box.

Many thanks, Garth!

Scott's HP-29C calculator surrounded by its box, manuals, charger, and more.

1977 era Hewlett-Packard 29C calculator in Kanata, Ontario, February 13, 2016. Photo by Garth Gullekson

A closeup of Scott's HP-29C calculator surrounded by its box, manuals, charger, and more.

1977 era Hewlett-Packard 29C calculator in Kanata, Ontario, February 13, 2016. Photo by Garth Gullekson

References: You can learn more about HP calculator history on the WIkipedia HP Calculators page and at hpmuseum.org.