DATAMATH CALCULATOR MUSEUM

Texas Instruments Business Card

Date of introduction:	1979	Display technology:	LCD
New price:	$44.95 (SRP Sep. 1980) $35.00 (October 1981)	Display size:	8 (5+2)
Size:	3.7" x 2.2" x 0.25" 95 x 57 x 6 mm³
Weight:	1.3 ounces, 38 grams	Serial No:
Batteries:	2*LR54	Date of manufacture:	wk 48 year 1979
AC-Adapter:		Origin of manufacture:	El Salvador
Precision:	11	Integrated circuits:	TP0325
Memories:	1
Program steps:		Courtesy of:	Joerg Woerner
		Download manual:	(US: 4.1M Bytes)

This stylish Business Card looks different to all but two Texas Instruments products we know. It is the rare sibling of the TI-1760 DataCard and the ultra-rare TI-1745 DataCard Time calculators introduced in 1979. Main difference is the additional row of keys and the 2ND-key never found in a "Basic" calculator and even scientific notation and an internal number representation with 11 digits resolution. Nevertheless put we this unusual Financial calculator in the "Basic" section of the Datamath calculator Museum.

A deeper exploration of the keyboard shows some financial function keys put as second function of the operation keys, a layout unknown with any other calculator developed by Texas Instruments.

Dismantling this Business Card calculator manufactured end of 1979 in El Salvador reveals a design very similar to the TI-1760 DataCard. We have no doubts that this unusual product uses a single-chip calculator circuit of the TP0320 family instead the simplified TP0311 family used with the Basic-line calculators. We know the TP0320 calculator chip from products like:

• TP0320   TI Investment Analyst
• TP0321   TI-50
• TP0322   TI-Business Analyst-II
• TP0323   TI-53
• TP0324   TI-35
• TP0326   TI-38 and TI-20

Please notice the gap in the list between the entries TP0324 and TP0326. With both the TI-35 and TI-38 introduced in 1979, we suspect that the Business Card calculator makes use of a TP0325 single-chip calculator circuit.

Find here an excerpt from the Texas Instruments Incorporated leaflet CL-199J dated 1981:

Business Card

Super slimline LCD for finance and business … with Constant memory* feature.

So lightweight and compact that you can take it anywhere. Features positive action keys designed to feel right to your fingers.
Conveniently arranged financial keys compute time and money problems. Profit margin calculations are rapidly handled with cost, sell, or margin keys.
On-the-spot answers become easier: Add-ons, discount percentages, reciprocals, squares, square roots, etc. Full arithmetic memory for added versatility.
TI’s Constant Memory* feature retains stored data, even when the calculator is turned off. APD* automatic power down feature. Up to 1,000 hours of normal operation from two miniature batteries.

* Registered Trademark of Texas Instruments Incorporated

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