Brand: | Hewlett Packard |
Model: | HP 35 |
Type: | Scientific calculator |
Pictures: | |
Batteries: | Battery pack |
Lifetime: |
Introduced: 1972 Terminated: 1975 |
Notes: |
Hewlett Packard's first pocket calculator and the very first scientific
pocket calculator. Apparently called the HP 35 because it has 35 keys.
In a time where other, often quite expensive, calculators could only do the standard four functions and sometimes a square root, Hewlett Packard was able to proce this beautiful calculator. This calculator doesn't have the complex look of later HP calculators because there are only three keys with double functions, ARC SIN, ARC COS and ARC TAN. Talking about those functions, there is only one angular mode available, DEGrees. Maybe an odd decision since PI is also available as a constant. Still, being able to produce a pocket calculator with these functions at all is a feat in 1972. Very powerful for its time, uses RPN and includes useful scientific functions such as trigonometric functions and their inverses (using the "arc"-key), natural logarithms and powers (using the "x^y"-key). As usual with the early HP calculators, this calculator as a very strong case and keys that simply won't wear out.
Something strange is going on with the second HP 35 in my collection,
the one shown on the right. When I found that one on a flea market I
first thought I had found an HP 80, HP's second pocket calculator.
On closer inspection however it
turned out to be a HP 35 with a "Hewlett • Packard 80" designation
on the front. According to other sources on the net, such as the
excellent site The Museum of
HP Calculators (link valid 2022-12-30), the designation should have
been "Hewlett • Packard" or "Hewlett • Packard 35" (like the
one on the left). There's some information on the HP 35 on HP's official website (link valid 2022-12-30). The Hewlett-Packard Company Archives site also has some information on this calculator, see Adding Innovation: The HP 35 (link valid 2023-01-07). The website vintagecalculators.com (link valid 2023-01-25) has a page with interesting information from the book "A Guide to HP Handheld Calculators and Computers," by Wlodek Mier-Jedrzejowicz. See this page (link valid 2023-01-25). For more information on this beauty please refer to the better sources, like The Museum of HP Calculators (link valid 2022-12-30). |
©2023 Ernst Mulder