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An extract from Audio Problem Solving with a Programmable Calculator, db the Sound Engineering Magazine, vol 13, no. 1, JAN 1979, pgs. 42-44

" … In this article, Maxwell's formulae will be converted into a program that can be run on a modern desk-top calculator. The specific program listed below was done on a Hewlett-Packard HP-97 calculator. The same program will run on the HP-67 with simply a change in notation, and can be translated for the HP-33E with a few significant changes. By following the program step-by-step, it is hoped that the reader will gain a better understanding of how the programmable calculator may be used for audio problem solving.
The program is presented in three columns; A, B, C. Column A is a tally of line numbers or "instructions." Each instruction is a key stroke(s), and these are listed in Column B. Where an instruction requires more than one key stroke, these are separated by a space in column B. Column C is a series of brief explanatory remarks, which are discussed in greater detail at the conclusion of the program.

Given below is a somewhat longer program for Maxwell's second set of formulae, which relate to the noise appearing in the output of a preamplifier when driven from a magnetic phono cartridge. This calculation is of course more complex, since both inductive and capacitive -as well as resistive- elements are involved."

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