DATAMATH CALCULATOR MUSEUM
Western Auto Citation aka 66-4986-7 (Version 2)
|Date of introduction:||1977||Display technology:||LED-stick|
|New price:||Display size:||8|
|Size:|| 5.4" x 2.8" x
138 x 72 x 32 mm3
|Weight:||3.0 ounces, 84 grams||Serial No:|
|Batteries:||9V||Date of manufacture:||wk 29 year 1978|
|AC-Adapter:||AC9180||Origin of manufacture:||USA (LTA)|
|Program steps:||Courtesy of:||Joerg Woerner|
With the discontinuation of the TI-1200 family in 1977, Western Auto consequently replaced the M4986 "Citation" calculators and its siblings M4987 and M4988 with products based on the TI-1000 family. While the backside of the revised "Citation" calculator is missing any reference to the previous M4986 designation, sports the sales box a part number 66-4986-7, obviously a reference to the original naming scheme. Please find in the table below a cross reference between Western Auto's 1976/1977 and 1977/1878 calculator offerings:
eye-catching "woody" design of the TI-1200 based M4986 "Citation" calculator was
dropped with its successor in favor of an elegant gray-white keyplate almost
matching the original TI-1000 look and feel. Other than that are the "Citation"
and TI-1000 identical, the back side of the calculators
tells you even its manufacturer Texas Instruments.
Dismantling the featured 66-4985-7 with Date code 2978 LTA and manufactured in July 1978 in Lubbock, Texas reveals a very efficient and cost-optimized design with a flexible single-sided printed circuit board (Flex-PCB) centered around a TMC1992 single-chip calculator circuit and powered by a 9V battery.
The TMC1990 calculator chips are based on the TMS0970 used with the TI-1200 family but integrate a power latch and power transistor to replace the original sliding power switch with two more cost effective [ON] and [OFF] keys.
Western Auto Supply Company ceased end of 1978 distributing "Citation" calculators manufactured by Texas Instruments, just 5 years after their journey began with the M4995 "electronic Wizard".
If you have additions to the above article please email: firstname.lastname@example.org.
© Joerg Woerner, January 4, 2002. No reprints without written permission.