DATAMATH CALCULATOR MUSEUM
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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 |
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| 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 VDD.
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.
© Joerg Woerner, December 5, 2001. No reprints without written permission.