Category: Calculators

In this category I will talk about very special calculators

SwissMicros DM15L firmware upgrade

SwissMicros DM15L firmware version

Determine your current version First take a look at the following DM15L link from the manufacturer to get started on the DM15L firmware upgrade.Then decide what version you want. Since I have the following Version, I decided to stay with the same, but upgrade it.The SwissMicros DM15L is the Replacement of the HP15C. On the …

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HP-28S Battery Compartment Door

Battery Door from right

HP-28S Battery Compartment Door The redesign of the whole HP-28S scientific calculator case is quite difficult and very time consuming. In most cases the only thing broken is the HP-28S battery compartment door, so I decided my first step was to get that re-designed. Print testing phase of battery door The 3D-print of the HP-28S …

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Permanent link to this article: https://www.teawea.com/hp-28s-battery-compartment-door/

HP Program Mortgage calculator

Mortgage program for HP28S

HP Program Mortgage calculator Formula The HP program mortgage calculator uses the following formula to calculate the mortgage payments:Payment = Price / [(1/I) – 1/{I*(1+I)^n}]I = Interest per month = yearly Interest / 12n = number of month Before you start, create a directory First make sure you are at HOME or root directory. You …

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Permanent link to this article: https://www.teawea.com/hp-program-mortgage-calculator/

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