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Subject: Re: Calculators
From: Tony (anthonys@XXX.XXX)
Date: Thu Sep 02 1999 - 00:23:19 EDT
Bill:
I'm not sure what your key points are here but I must say that sun almanacs
are the easiest to program, with stars following close behind. It's the
"other buggars" that become very difficult in terms of memory and accuracy.
:-) Would you agree?
Tony
Bill Murdoch wrote:
>
> I have had a good time playing with the Texas Instrument calculators. They
> are inexpensive, easy to program, and readily available. I have TI-67 Galaxy
> that I bought new for UKL 17. The February 1994 copy of Practical Boat Owner
> has an article which contains a sun sight reduction program for that
> calculator. I also have a TI-81 and wrote a similar program for it. That
> program was published in the March 1996 issue of Cruising World. I have
> modified the sun sight program for the TI-82 and TI-83. If you wish can send
> you a copy. The program contains a 0.1', 200 year solar almanac. Given the
> time and date, the sight data, and the DR, it returns the azimuth and
> intercept.
>
> I also wrote a much longer nav program for a TI-82 which has almanacs for the
> sun, moon, four planets and 92 stars. It has all be bells and whistles -
> unknown bodies, mercator and spherical sailings, sun rise and sun set, etc.
> I sold copies for a few years of the typed program and of the program on
> diskette (the diskette can be loaded on the calculator through a PC).
>
> I learned a lot writing the programs. I had a good time doing it. The TI
> calculators use a language much like Basic and can be programed either
> through their keypads or through a PC connected to the calculator with a
> TI-Graphlink cable. The math is tough, but people did it in the 1800s with
> little more than logarithm tables.
>
> Bill Murdoch
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