Texas Instruments TI-2600 Personal Banker

The Personal Banker followed the BA-SOLAR and uses four different Help Cards to answer financial questions with ease and convenience. The picture on the left shows from top to bottom:

These cards can be rearranged if one application is used more often than the others. 

The five financial keys, located on the right side of the calculator, correspond with the values in a financial problem. When a financial key is pressed, a corresponding indicator appears at the bottom of the display, and the number in the display is stored in the financial registers.
Pressing the [SOLVE] key followed by the financial key that represents the unknown value solves the financial problem. With the [RECALL] key followed by a financial key, the values from the financial registers could be reused in other calculations.

The innovative clamshell design of the Personal Banker allows its use as a compact four function calculator, too.

Dismantling this Personal Banker manufactured in November 1987 by Inventec Corporation in Taiwan reveals a very clean design centered around an unknown Toshiba single-chip calculator circuit soldered on a double-sided printed circuit board (PCB) and powered by two small LR44 batteries. The five extra financial keys and [SOLVE] / [RECALL] keys are connected with a flexible PCB to the main electronics.

Inspecting the PCB of this Personal Banker calculator brought our attention to a small mark reading IOPERSONAL BANKER-31D, we noticed similar marks already with other calculators manufactured by Inventec Corporation and started compiling a list of the PCB-Marks on calculators manufactured by OEMs for Texas Instruments.

Another approach of a new human interface was developed with the Business Edge in the same year. This financial calculator features five pressure-sensitive areas on the LCD-screen and displays the actual function under these squares. The later SC-10 used the right half of the foldable housing for a lot of scientific keys. 

Texas Instruments launched in 1987 a very innovative product line with the TI-2400 Phone Bank, TI-2600 Personal Banker, TI-2700 Mini Data Bank, and TI-2800 Paperless Printer followed till 1990 with the TI-2100 Pocket Info, TI-2900 Info Bank, TI-3100 Pocket Dialer, TI-3200 Pro Dialer, and TI-3400 EUROPA.

If you know the history of Texas Instruments it seems to commemorate the introduction of the TI-2500 Datamath a quarter century ago.

If you have additions to the above article please email: joerg@datamath.org.

© Joerg Woerner, July 22, 2002. No reprints without written permission.