Hewlett Packard - HP 25


Brand: Hewlett Packard
Model: HP 25
Type: Programmable scientific calculator
Picture: HP 25
Batteries: Battery pack
Lifetime: Introduced: 1975
Terminated: 1978
Notes: The funny thing about the early HP calculators is that when you first see them you think it's an ordinary calculator, but when you look more closely you realise that they are sophisticated programmable calculators with only a few buttons.

This is one of those kinds of calculators. I wish they would produce calculators like this one nowadays. It's small, it has most of the required functions, is easy to use and it uses RPN. What more does one want?

The only possible drawback of this calculator is its LED display and its volatile memory. That's why the HP 25C was introduced in 1976 which has constant memory.

For more information on this beauty please refer to the better sources, like The Museum of HP Calculators (link valid 2022-12-30).


A power adapter.

©2023 Ernst Mulder