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Articles on the HP-45

Using an example, this article from 1976 shows how the HP-45 computes the cosine of an angle. In German only, unfortunately, but with the help of the pictures, formulas and tables you may get the idea.

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In 1976, some clever tinkerers added programmability to the HP-45. In German only.

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A paper written by Hewlett-Packard in 1974, praising the virtues of RPN.

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In 1976, Egbert Electronics from Orem, Utah, offered a quartz kit for the HP-45. It cost $13. Here are the installation instructions.

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Internet Links, Quick Reference Guide

HP-45 Quick Reference Guide
The original reference guide that came with the HP-45. This early edition contains errors on pages 5 and 6, corrected in later editions.

HP-45 Owner's Handbook now as color PDF
An early edition of the user's manual. You may want to check out the Addenda below.
(Note that the result given on page 7 is wrong. The last three digits should be 225.)

HP-45 Owner's Handbook Addenda
This sheet explains register arithmetic added to later models of the HP-45.

HP-45 Applications Book now as color PDF
A wonderful book written by Hewlett-Packard Advanced Products Division, giving step-by-step solutions to more than 200 problems in mathematics, statistics, finance, engineering, navigation plus tips on more efficient calculator operations.

HP-45 Key Sequence Form new
A form in PDF format for documenting reusable key sequences.

The number one URL for all things "HP calculators". At http://www.hpmuseum.org/simulate/sim45.htm there's even a Java application simulation of an HP-45 based on the real ROM microcode.
Manuals (and much more) may be purchased here: http://www.hpmuseum.org/cd/cddesc.htm

Good article about Reverse Polish Notation.

A browser-based simulation of the HP-45, written in JavaScript. Runs fine on Firefox – Safari and Google Chrome, however, report a type error, refusing execution. Not a perfect simulation, but a good example of the power of JavaScript (http://www.t-denker.de/hp45/hp45.750.js).




HP-35 in Popular Electronics (1972)
A very early review of the HP-45's predecessor.

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