DATAMATH  CALCULATOR  MUSEUM

Texas Instruments SR-40 LCD

Date of introduction:  1980 Display technology:  LCD
New price:   Display size:  8 (5 + 2)
Size:  5.3" x 2.9" x 0.95"    
Weight:  6.0 ounces Serial No:  75329
Batteries:  2*AA Date of manufacture:  mth 08 year 1983
AC-Adapter:   Origin of manufacture:  Brazil
Precision:  11 Integrated circuits:  
Memories:  1    
Program steps:   Courtesy of:  Joerg Woerner 

SR-40-LCD_Disp.jpg (45384 Byte)Fellow collector Paulo Rogerio Romagna, Brazil donated recently this wonderful and rare SR-40 LCD. Thanks! 

SR-40_LCD.jpg (64010 Byte)At first glance the SR-40 LCD manufactured in Brazil seems to be identical with the first version of the European TI-30 LCD. The picture on the right demonstrates that even the different versions sporting either the x!-key instead the later n!-key are known. 

Inserting the two AA-sized batteries into the convenient compartment on the back of the calculator was a great surprise - instead the wellknown sliding cover of the TI-30 LCD a coin is necessary to access the batteries. Comparing the two calculators reveals lots of differences between them, only few parts are really identical. 

Please watch the next pictures carefully to get an idea of the differences:

Instead of the plastic shell delivered with the TI-30 LCD a nice and valuable leather pouch keeps the SR-40 LCD clean and nice.  SR-40-LCD_1.jpg (148102 Byte)
The battery compartment of the SR-40 LCD could be opened with a coin.

SR-40-LCD_Batt.jpg (66331 Byte)

The side-view of the SR-40 LCD is completely different to the TI-30 LCD. Please notice the strange wedge shape known from the SR-10. SR-40-LCD_Side.jpg (19019 Byte)


Why all these differences ? Main reason is the restricted market access to Brazil !

In the 1980's (and even today) Brazil maintained various barriers to trade of both a tariff and a non-tariff barrier nature. A significant number of tariff peaks existed and the tariff structure showed tariff escalation for all industries, with a higher tariff on finished goods than on semi-processed goods and raw materials. 
The main non-tariff trade irritants included restrictive and non-transparent import licensing, imposition of minimum prices, restrictions to payment of imports, unnecessarily burdensome and costly customs procedures and protection of geographical indications. There was lack of transparency regarding applicable rules and many elements of the trading regime appeared unnecessarily trade restrictive. 
In addition, customs duties of some products remained on restrictive levels and the adverse effect of duties was further amplified by imposition of various charges and taxes that are calculated on top of the duty paid value.

One common solution was an off-shore production of either completely knocked-down-goods or a mixture of foreign and local material. 

SR-40-LCD_PCB.jpg (32952 Byte)Texas Instruments licensed the SR-40 LCD to Indústrias Gerais da Amazonia S.A. and supplied e.g. the printed circuit board (PCB), the single-chip calculator circuit and the keyboard to them. 

Other components like the housing and leather pouch were locally sourced by Indústrias Gerais da Amazonia.

Don't miss the SR-56, TI-30, Money Manager and TI-55-II manufactured by Texas Instrumentos Eletrônicos do Brasil Ltda. - Campinas.

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

© Joerg Woerner, April 30, 2004. No reprints without written permission.