DATAMATH

DATAMATH CALCULATOR MUSEUM

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, 2SN75491, 2SN75492
Memories:		Displays:
Program steps:		Courtesy of:	Peter Muckermann

This boxy calculator followed the EC-100 and doesn't look like a Texas Instruments product.

To identify it you should compare it with the Montgomery Ward P800 or the Longines Symphonette Electronic Calculator.

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.

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 MOS-IC	MOS-IC Datecode	MOS-IC ROM-Code
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

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