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Hewlett Packard HP-18C Business Consultant

• Type: Semi-algebraic Financial Calculator
• Size: 6 x 3.75 inches / 15 x 9.5 cm
• Size (open): 6 x 7.5 inches / inches / 15 x 19 cm
• Serial number: 2638A33594
• Date of Manufacture: September 1986

Accessories:

• Hewlett Packard 82240A Infrared Thermal Printer

Case considered superfluous.

I've naturally been more attracted to scientific calculators than financial calculators, due to my background in mathematics and engineering. This calculator, however, deserves special mention as it was the first of the Clamshell series offered by HP. That also makes it the first RPL calculator, although this model is not programmable. See my 28C and S page for more about the physical unit.

This was HP's first financial calculator after the 12C was introduced. The 18C was nonprogrammable and had onlly 4 general purpose registers, but it had more memory for cash flow calculations and included HP's famous Solver. Most functions on the 18C are stored in the menu system. (I didn't mind the menu system when I got my 28 but, for some reason, the menus on the 18C aren't as satisfying as having all the functions on the keypad as on the 12C. Please note that HP still (as of 2006) sells the 12C despite faster menu-based financial calculators being available.)

The 18C quickly yielded to the the 19B, introduced in 1988.