Radio Shack EC-200

Date of introduction:  October 1973 Display technology:  LED-modules + lens
New price:  $89.50 Display size:  8
Size:  5.8" x 3.5" x 1.8"
 148 x 88 x 45 mm3
Weight:  7.4 ounces, 211 grams Serial No:  A2 039058
Batteries:  4* AA or NiCd AA Date of manufacture:  mth 11 year 1973
AC-Adapter:  unknown Origin of manufacture:  USA
Precision:  8 Integrated circuits:  TMS0109 or TMS0103, 2*SN75491, 2*SN75492
Memories:   Displays:  
Program steps:   Courtesy of:  Peter Muckermann

EC-200_1.jpg (23589 Byte)This boxy calculator followed the EC-100 and doesn't look like a Texas Instruments product. 

First_TI.jpg (52283 Byte)To identify it you should compare it with the Montgomery Ward P800 or the Longines Symphonette Electronic Calculator.

EC-200_2_SN4442.jpg (56517 Byte)If you look deeper into the calculator you'll notice that the EC-200 is very similar to the TI-2500 Datamath but uses with the TMS0103 an other member of the TMS0100 single-chip calculator circuit family. A later model with serial number A2043934 manufactured in 1974 uses a TMS0109 chip.

This Radio Shack EC-200 is once again a calculator using the famous Texas Instruments Klixon™ keyboard technology.

EC-200_Switch.jpg (59513 Byte)The battery compartment of the EC-200 sports a small sliding switch to select between "RECHARGABLE NI-CD BATTERIES" and "ALL OTHER BATTERIES". This switch prevents the AC-Adapter from providing a charge to the batteries if the switch is set to "ALL OTHER BATTERIES".

With the EC-300 a great change in the design of the calculator happened.

Datamath™ and Klixon™ are trademarks of Texas Instruments.

Known serial numbers:

Serial Number Calculator 
A2 4442 TMS0103 7307 ZA0067
A2 4801 TMS0103 7250 ZA0067
A2 9215      
A2 24407 TMS0109 7315  
A2 039058       
A2 043934       
A2 044598 TMS0103 7328  
A2 048739 TMS0103 7328  

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