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DATAMATH CALCULATOR MUSEUM

Western Auto electronic Wizard aka M4986 (Version 2)

Date of introduction:	August 1975	Display technology:	LED-stick
New price:		Display size:	8
Size:	5.5" x 2.8" x 1.4" 138 x 70 x 35 mm³
Weight:	3.9 ounces, 110 grams	Serial No:	0112593
Batteries:	9V	Date of manufacture:	wk 07 year 1976
AC-Adapter:	AC9180	Origin of manufacture:	USA
Precision:	8	Integrated circuits:	TMS0952
Memories:
Program steps:		Courtesy of:	Joerg Woerner

The original design of the M4986 was only manufactured for a few months, Texas Instruments changed the PCB slightly to accommodate four additional 330Ω resistors to pull down the four keymatrix input lines of the TMS0952 Chip to V_DD.

Dismantling the featured M4986 with Date code 0776 LTA and manufactured in February 1976 in Lubbock, Texas reveals a very efficient and cost-optimized design with a single-sided printed circuit board (PCB) centered around a TMS0952 single-chip calculator circuit based on the TMS1000, the World's first Microcomputer.

The TMS0952 was soon replaced with the TMS0972, a pin-compatible design dropping the additional resistors and capacitor and further reducing the manufacturing costs of the M4986 series. The name of the M4986 was changed from "electronic Wizard" to "Citation".

Learn more about the evolution of the TI-1200 between March 1975 and its discontinuation in 1977.

Learn more about the different Product Labels used with the TI-1200 - here at the Datamath Calculator Museum we classify the featured M4986 as Hardware Version 2, PCB Type 2 and Product Label Style 3, Western Auto.

Note: We assume that the featured calculator is missing its "electronic Wizard" sticker next to the LED display.

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