HP 65 programmable


My dad showed me the method of successive trials to solve intractable problems. When I had my HP65 I found I could enter the variables in storage and do a repeatted solution without effort. I was working with negatice temperature coefficient thermistors and had tabulated resistances but no formula. I tried until I found that adding a large number to the temperature and take the Ln I could match the slope of the resistance temperature curve over the complete range. I could refine the precision by repeated trials. To date this has not been discovered, but an extremely compleex method is used and they are not going to change. I thought I could match other graphs I used in electrical engineering and by trial and error matched many of them. I was interested in retirement and matched income tax in my renge, and made varied assumptions of inflation, return on investments, raises and solved them year by year. I found all you needed was to make more money than you spent and you could pay your way. I did not depend on SS or retirement benefits, I thought them unworkable schemes. So I'm good at 82 and will leave an income for my niece to sustain her.


There were programs for most HP programmables to do curve fitting, including logarithmic curves. It sounds like that was what you were doing manually.

As far as I can see, if you don't make more money than you spend, there isn't any retirement plan that will work.


If simple regression analysis would do it, they would not be using a complex solution (from the factory). What I was illustrating was that the ease of repeated trials can enlarge the range of problems you can undertake. "Go where no man has gone before." Sam a chum said If sidney darlington can have a coupound transistor namedafter him, we should be able to name a compound FET after you. Har Har.



I found all you needed was to make more money than you spent and you could pay your way.

IMHO, by your experimental method you found the basic law of living, also applicable beyond - ummh, before retirement. I suggest we call it Sam's Law from now on.

Happy and prosperous New Year!


I found all you needed was to make more money than you spent and you could pay your way.

May we all always be able to make more money than we need to spend.

Happy new year!

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