WG&L incotax (1981,82) calculator by Texas Instruments

Date of introduction:  1981 Display technology:  LED-stick
New price:   Display size:  10 (8 + 2)
Size:  6.4" x 3.2" x 1.5"
 162 x 81 x 37 mm3
Weight:  8.5 ounces, 240 grams Serial No:  1002659
Batteries:  BP1A Date of manufacture:  wk 29 year 1980
AC-Adapter:  AC9131 Origin of manufacture:  USA (ATA)
Precision:  13 Integrated circuits:  TMC0501E, TMC0580 (CD2400), TMC0580 (CD2401), TMC0573, TMC0591, Toshiba TC5047AP
 TMC0540 (CD5704)
Memories:  0-60    
Program steps:  480-0 Courtesy of:  Joerg Woerner

The innovative TI-58C was the perfect base for a lot of customized calculators. The idea behind these products was the novelty of the Solid State Software Modules™ with up to 5000 program steps.

The incotax application was developed by the Bureau of National Affairs, Inc., Washington D.C. to calculate Federal Income Taxes and distributed by Warren, Gorham & Lamont, Valhalla NY (WG&L).

The different programs of the incotax application used various overlays to the already modified calculator keyboard of the TI-58C.

Don't miss the 84' edition of the WG&L incotax calculator and the WG&L incotax 1985 calculator sporting an external program module.


Warren, Gorham & Lamont, Valhalla NY was founded in the 1950s, but traces its roots back to 1882, when Willard Warren started a weekly, the Connecticut Real Estate Record and Building News (later and still today, The Commercial Record). The Thomson Corporation acquired Warren, Gorham & Lamont (WG&L) in 1980. For more than three decades, WG&L was a major information source for finance professionals in companies of all sizes and industries. The WG&L product line includes some of the most valued newsletters, journals and treatises in the legal, tax and accounting fields. WG&L remains one of the most respected brands in the industry. In 1996, the tax publishing activities of Warren, Gorham & Lamont were merged with RIA.

WG&L ® is a trademark of Warren, Gorham & Lamont, Valhalla NY.

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© Joerg Woerner, November 20, 2013. No reprints without written permission.