Exactra 19 by Texas Instruments 

The Exactra series was introduced 1974, five modells were reported. The Exactra calculator does not use the name of the manufacturer on it's nameplate, you have to read the small printed on the reverse. The reasons are not clear, let us asume that in the middle of the decline of the prices the marketing guys tried to establish a low-budget line. Ironically in Europe similar calculators were sold as regular TI-1900 (not yet confirmed) and TI-2000 models.

The differences between the calculators are minor, the cheaper one use a 6-digit display, higher numbers use a 8-digit display. To reduce manufacturing costs the keys of the Exactra 19 use a single-shot instead a double-shot injection molding found at the sibblings.

 

The printed circuit board (PCB) of the Exactra 19 makes use of the TMS0806 single-chip calculator circuit and a tiny display driver. The remaining parts form a small power-converter to use the 3 AA-sized batteries instead a 9V battery block.
Please notice that the Exactra 19 uses a single-sided PCB instead the double-side boards of the Exactra 20.

An external power supply was only possible on the Exactra 22 and Exactra 23 models.

A clone of the Exactra 23 was sold from Montgomery Ward with the P100 model.

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

© Joerg Woerner, December 5, 2001. No reprints without written permission.