Sharp EL-8200 financial calculator questions

[robve]

(05-21-2023 02:08 PM)AndiGer Wrote:  As I "unearthed" a Triumph-Adler 84F lately and wanted to know how to operate it I did some research and found the Qualitron 1439 / 2139 Financial Calculator Manual at Katie's website which has the same keys (and as I found the Silver-Reed SR-85 as well).

Your EL-8200 looks very similar. But I haven't found the "n,x,x2" key on neither the 84F nor the Qualitron.
But for your question concerning Trend/TL I think this manual would be of (some) help.

https://www.wass.net/manuals/Qualitron%202139.pdf

Fantastic! The similarity is spot on! Thanks a lot for pointing in the right direction

The Sharp EL-8200 has exactly the same functions as the Qualitron 2139. I ran thought the manual and the examples. It is basically the same calculator. The only difference is that the Sharp's TAB and n,x,x² keys are labelled DS and ∑ on the Qualitron. The EL-8200 was introduced in 1975 and precedes the Qualitron 2139 by one year, according to https://www.calcuseum.com.

I found the answer to the TL and Trend functions. ENT Trend with COMP TL (trend line) give the intercept and slope of the trend line of a set of equidistant points, such as annual sales. It can also interpolate any given point with ENT n and COMP Trend.

Fortunately, and contrary to what I stated earlier, this calculator can in fact solve for "n" and interest "i". Even better, it supports amortization and can return the interest paid for a loan for a given period and annually (example shown on the last page of the manual).

I like this unusual financial calculator. It is quite capable with a few key presses, if you know how

- Rob