I have an older version 1999 of the ElectriCalc Pro calculator. They have an upgrade kit for 2005. I don't see how to install it, unless I have to pull the back cover off. But it doesn't look like it would fit inside.
$39.95 upgrade kit.
$89.95 new calculator 2005
It looks like you replace the back cover with the new one. Check here
http://www.constructionbook.com/xq/ASP/ProductID.4206/id.458/qx/default2.htm When in doubt do a GOOGLE
I don't think so on mine, maybe it works with the "LT" version. Looks like it has a snap-in chip. Don't think mine is.
I have the model 5055 ElectrCalc Pro, looks like I need the model 5060 to upgrade the chip.
Al D
What could have changed in what your calculator has in it? Tables haven't changed have they? None of the other calcs for VD, or amperage have changed have they? So what is different in the calculator for '99, and the up-grade chip?