By 1990 the American educational market for graphing calculators was highly competitive. Early that year Texas Instruments introduced its first graphing calculator for classroom use, the TI-81. A special overhead projection unit of the calculator was available, and advertisements showed a teacher displaying calculator results on a screen, with fascinated students comparing her work with the displays of their own calculators. By November, Casio sold a modified form of its FX-7000G calculator for use with an overhead projector, the OH-7000G. This is an example of that device.
The overside handheld electronic calculator has a gray plastic case, a silver-colored metal keyboard with plastic keys, and a translucent glass display screen above the keyboard. The keys are like those of the fx-7000G. A mark above the keyboard reads: CASIO SCIENTIFIC CALCULATOR OH-7000G GRAPHICS.
The back of the calculator has room for four batteries in a compartment at the base. The screen is at the top and there are four rectangular feet. A mark above the battery compartment reads: CASIO 0H-7000G (/) RATING: DC 6V = 0.04W (/) use BATTERY 1.5v x 4 (/) MADE IN JAPAN (/) CASIO COMPUTER CO., LTD.
The calculator fits in a gray plastic case with a snap.
The metal and glass projection unit, made by Buhl, fits in a blue cloth bag.
References:
“Introducing the TI-81 Graphics Calculator. An educated solution tailored to educational needs [advertisement],” Mathematics Teacher, vol. 83 #4, April, 1990, front matter.
“The Power to Project Your Ideas [advertisement],” Mathematics Teacher, vol. 83 #8, November, 1990, front matter.
Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.
If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.