DATAMATH  CALCULATOR  MUSEUM

Original Equipment Manufacturers (OEMs)

Made in the USA - this is how Texas Instruments started in 1972 with the introduction of the famous TI-2500 Datamath, TI-3000, and TI-3500 calculators. The last TI calculator manufactured in Lubbock, TX? The TI-7000 II, TI-7140, and TI-7300 II manufactured in 1994 for Texas Instruments' US-built campaign started in 1989.

 Vertical Integration

Caltech2_large.jpg (59964 Byte)When Jack S. Kilby, an Inventor of the Microchip, initiated in 1965 the Cal-Tech project, he and and two of his colleagues, Jerry D. Merryman and James H. Van Tassel started literally from scratch. There was no such thing like compact and power conserving LED displays or cost effective keyboards and Texas Instruments decided to develop all core technology other than the rechargeable batteries for the Cal-Tech project in-house.

Texas Instruments approached Canon Inc. (Tokyo) and arranged to coproduce a pocket calculator completely built with Texas Instruments parts. In April 1970, the Pocketronic appeared on the Japanese market; it was a four-function, entirely electronic calculator that retailed for about $400. Texas Instruments announced on September 17, 1971 with the TMS1802 a single-chip calculator circuit and offered it together with four integrated display drivers, two integrated LED display modules, a complete keyboard assembly and even schematics for a fully functional, battery operated calculators to various OEMS.

Bowmar announced in the same month the game-changing 901B "True-Pocket-Size" calculator based on the TMS0103 single-chip calculator circuit (a variation of the TMS1802), Texas Instruments' Klixon keyboard assembly, TI display drivers and their own LED displays. Dozens of other companies followed with more or less success before TI introduced on September 21, 1972 formally the TI-2500 Datamath.

A perfect example of Vertical Integration:

TI-2500 Calculator assembly: TIs Dallas facility
TMS0100 MOS/LSI calculator-on-a-chip: TIs Houston plant
1KS/6KS Klixon keyboard: TIs Attleboro facility
TIL-360 LED-display modules: TIs optoelectronic department in Dallas
Plastic cases molding: TIs Sherman facility

 Texas Instruments and Toshiba

While Texas Instruments was a pioneer of early calculators based on thermal printer and LED display technology, were companies in Japan forerunners in combining both LC-Displays with single-chip calculator chips manufactured in low-power CMOS technology. Think about the groundbreaking Sharp EL-805 introduced in May 1973 and both Canon LC-1 and Toshiba LC-810 introduced in 1976 - almost one year ahead of TI's TI-1750. The TI-1750, introduced in April 1977, started an era of a productive cooperation with Toshiba that brought us not only the TI-1790 Datachron, TI-25 and TI's first solar cell powered calculator (TI-1766) but even the amazing TI-66 Programmable. Visually compare some Toshiba and Texas Instruments calculators. Texas Instruments could bridge their technology gap in CMOS technology with their cooperation with Toshiba before introducing in June resp. August 1978 basic, scientific, and financial "slimline" calculators sporting LC-Displays "Made in the USA": TI-1030, TI-50, and Business Analyst II.  


 Original Equipment Manufacturers (OEMs)

We wrote the year 1981 when Texas Instruments introduced with the TI-55-II the first product of a very sophisticated calculator line positioned above the "slimline" series from 1978. These calculators combined an innovative architecture with a Master and Slave CPU and an enhanced LC-Display with the keyboard technology from the original slimline series. Unfortunately led some cost reduction measures of the keyboard design to an extremely unreliable design and there was immediately a saying: "The -II designation was evidently for the number of keystrokes that were recorded with one button press".

Texas Instruments was during this difficult time already experienced with contract manufacturers in Far East - we noticed TI-1015 and TI-1020 calculators assembled in Taiwan with date codes as early as 1980 - and it wasn't too big of a surprise to see the second series of the TI-55 II manufactured starting Summer 1984 by Inventec Corporation in Taiwan with a completely different "Asian-style" keyboard. Inventec was in 1984 the largest calculator producer in Taiwan and expanded soon into Malaysia to take advantage of competitive labor rates. In 1995 the first factory was established in Shanghai, China - manufacturing most of TI's graphing calculator line - before further expanding in China in 2004 to add even engineering services and a logistics center to the then 8 factories. Texas Instruments was and is working with other contract manufacturers, too - we know as of today:

Calc-Comp Electronics - Thailand
Compal Electronics - Taiwan, China
Inventec Corporation - Taiwan, Malaysia, China
Kinpo Electronics - Taiwan, China, Philippines
Leo Electronics - Japan, China
Nam Tai Electronics - China
Zeny Corporation - Taiwan, China

We consider these companies "Contract Manufacturers" understanding that the services provided expanded in the past Decades significantly into providing engineering, testing, repair and logistics services. Looking closely at some Texas Instruments calculators from the Eighties you'll notice some outlier not following the typical 4-digit "Far East" date code like I-1086: Inventec October 1986.

Examples are this TI-1756 with serial number 8687189 and this TI-2200 Checkwriter with serial number 84249159. Dismantling these two calculators revealed a surprise, we located on the printed circuit boards (PCBs) small marks reading MK65 resp. 309T-10. We located similar PCB Marks on almost identical looking products from other brands and would call it "Badge Engineering".

The near identical offspring of the TI-1756, the IMA LC 688, Novus Electronics NS220 and Unisonic LC-7311BK consequently exhibit the MK65 PCB-Mark, too while we could trace back the 309T-10 PCB-Mark from the TI-2200 Checkwriter to the Radio Shack EC-306 sporting a 306 PCB-Mark.

Tracing back to Texas Instruments' OEMs is pretty straight forward for most calculators and related products manufactured in or after 1984 - the date codes on the back of the products display usually the contract manufacturer, e.g. I for Inventec Corporation Taiwan / Malaysia or P for Inventec Pudong Campus in Shanghai, China. The difficult part is with the numerous TI calculators introduced around 1982 sporting just a serial number, don't miss our tear-down of the TI-1755 SLR and its relative SL674CK from Technico, a brand of Inventa Electronics Co., digging even into the fonts used with the calculator keys.

Printed Circuit Board Marks (PCB-Marks)

We noticed during our research of calculators a huge variety of PCB-Marks and compiled a first overview (Work-in-Progress):

(Unknown OEM - Compal Electronics?)

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code

Country of Manufacture

306 01 NEC uPD1833G Checkbook,
3 Memories
Radio Shack EC-306 1A5
Jan. 1985
Hong Kong
306 02 NEC uPD1833G Checkbook,
3 Memories
Tandy EC-306 1A6
Jan. 1986
Hong Kong
307 10 Sharp LI3330MT Checkbook,
1 Memory, TAX
Royal CBC 70
Unisonic LC 226CK
Nov. 1988
Aug. 1991
Taiwan
Thailand
308 15 Toshiba T7752S Checkbook,
3 Memories
TI-2200 II C-0695
Jun. 1995
Thailand
308 16 Toshiba T7752S Checkbook,
3 Memories
Royal CBC 80NT
Unisonic LC 266CK
1987
1987
Taiwan
308 17 Toshiba T7752S Checkbook,
3 Memories
Royal CBC 80 1988 Thailand
308 18 Toshiba T7752S Checkbook,
3 Memories
Royal CBC 80
Royal/Olivetti CBC 80
Olivetti DII
Royal CBC 95
1989
1990
1990
1995
Thailand
308-II 02 Toshiba T7752S Checkbook,
3 Memories
TI-2200 II C-0387
Mar. 1987
Taiwan
309T 10 NEC uPD1833G Checkbook,
3 Memories
TI-2200
TI-2200 II (EU)
Dec. 1982
Oct. 1984
Taiwan
310 2 NEC uPD1832G Checkbook,
1 Memory
Unisonic LC 224CKE Sep. 1983 Taiwan
310S 10 Sharp LI3329MT Checkbook,
1 Memory
Unisonic LC 224CK Sep. 1983 Taiwan

 

(Inventec Corporation)

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

IO074D 05C Sharp LI3033M Basic
Style
Technico LC-74CK
Version 2
---
Mar. 1985
Taiwan
IO74F 02B unknown Basic
Style
Technico LC-741CK ---
1984
Taiwan
IO0601C 01A unknown Basic
Style
Technico LC-601 ---
Sep. 1983
Taiwan
IO0612A 01C unknown Basic, Solar
Style
TI-1757 II ---
ca. 1983
Taiwan
IOSL656C 02G Toshiba T6853BU Basic, Solar
Style
Technico SL-656 ---
May 1986
Taiwan
I6745A 02B unknown Basic, Solar
Style
Olympia SL674CK 3251548
ca. 1983
Taiwan
I674C 05G unknown Basic, Solar
Style
IMA LC 685S ---
Jul. 1983
Taiwan
I676B 01C unknown Basic, Solar Technico SL-676CK ---
May 1984
Taiwan
I677A 01D unknown Basic, Solar Technico SL-600 ---
Mar. 1986
Taiwan
IO0800
O810
02D
02B
Toshiba T6853BU Basic, Solar
Foldable
Technico F-800

TI-2130
---
Nov. 1984
I-0985
Sep. 1985
Taiwan

Taiwan
10SB863 01B Toshiba T9731BU Desktop, Solar TI-1798

TI-510

TI-1798
I-0990
Sep. 1990
I-1290
Dec. 1990
I-0391
Mar. 1991
Taiwan

Malaysia

Malaysia
ISB867 01E

02A
unknown Desktop, Solar Technico SB-867

Technico SB-867N
---
Oct. 1986
---
Mar. 1987
Taiwan

Taiwan
I881B 01C unknown Desktop, Solar Technico SL-881 ---
Oct. 1985
Taiwan
IO01027 02B unknown Desktop, Solar Technico SB-1027 ---
Oct. 1985
Taiwan
IOPD2003 01C unknown Desktop, Printing Technico PD-2003 ---
Jul. 1985
Taiwan
BA20 PCB VER0.3 Inventa LI3163 Desktop, Solar BA-20

BA-20
S-0400A
Apr. 2000
S-0500
Mai 2000
China

China
BA20N PCB VER0.1 Inventa LI3163 Desktop, Solar BA-20 S-0307C
Mar. 2007
China
IOBA20 01C Sharp LI3163 Desktop, Solar
(Clock Module)
BA-20 I-0686
Jun. 1986
Taiwan
IOBA20 02A Inventa LI3163 Desktop, Solar
(Clock Module)
BA-20

BA-20
C-0790
Jun. 1990
I-0990
Sep. 1990
Taiwan

Taiwan
IOBA20 02B Inventa LI3163 Desktop, Solar
(Clock Module)
TI-620

BA-20
I-1293
Dec. 1993
I-0897
Aug. 1997
Malaysia

Malaysia
IBA35 01C CD4571 Finance BA-35 I-0784
Jul. 1984
Taiwan
BAIII 01D

01F
TP0322 Finance BA-III Prototype

BA-II
-----
Dec. 1985
I-0385
Mar. 1985
Taiwan

Taiwan
IOPERSONAL BANKER 31D Toshiba Txxxx Finance Personal Banker I-1187
Nov. 1987
Taiwan
IOSC10 21B Toshiba Txxxx Scientific SC-10

Collegiate
I-0188
Jan. 1988
I-0988
Sep. 1988
Taiwan

Taiwan
IOST412 31D Toshiba T9728 Finance Business Edge I-0188
Jan. 1988
Taiwan
IOTI10 02A unknown Basic, Solar TI-10 I-0786
Jul. 1986
Taiwan
IOTI108A 02A unknown Basic, Solar TI-1105 I-0288
Feb. 1988
Taiwan
IOTI108D 01B unknown Basic, Solar TI-108 I-0888A
Aug. 1988
Taiwan
IOTI108E 01A unknown Basic, Solar TI-108 I-0989A
Sep. 1989
Taiwan
10TI611A 02A unknown Desktop, Solar
(Clock Module)
EUROPA 10 I-0694
Jun. 1994
Malaysia
10TI611DAMB 31B unknown Data Bank
Design
TI-3400 EUROPA I-0490
Apr. 1990
Taiwan
I1100 01H Toshiba T6717AS Basic TI-1100 I-0284
Feb. 1984
Taiwan
ITI1100
ITI1101
02A
02A
Toshiba T6958S Basic TI-1100 Prototype I-1084
Oct. 1984
Taiwan
IOOTI1100 02D Toshiba T6958S Basic TI-1100 II I-0385
Mar. 1985
Taiwan
IOTI1100IIIA 01A unknown Basic TI-1100 II I-1089
Oct. 1989
Taiwan
IOTI1103A 01A unknown Basic Number Beat I-0687
Jun. 1987
Taiwan
IOTI1105 01C unknown Basic, Solar TI-1105

TI-1105
I-0687A
Jun. 1987
I-0787A
Jul. 1987
Taiwan

Taiwan
I1706 01K Sharp LI3129 Basic, Solar TI-1706 I-0384
Mar. 1984
Taiwan
TI1746 01C unknown Basic, Solar TI-1746

UNIS SLR 80
I-0385
Mar. 1985
---
(32112)
Taiwan

Yugoslavia
ITI1755 01D unknown Basic, Solar
Style
TI-1755 SLR (552243) Taiwan
IOTI1766IIIMB 01F unknown Basic, Solar TI-1766 III I-0592
May 1992
Malaysia
IOTI1775 21A Toshiba T9731BU Basic, Solar
Foldable
TI-1775 I-0192
Jan. 1992
Malaysia
IOTI1796 01A unknown Desktop, Solar
(Clock module)
TI-1798

TI-1796
C-0185
Jan. 1985
I-1186
Nov. 1986
Taiwan

Taiwan

 

(Unknown OEM - Inventa Electronics Corporation?)

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

MK65 6 Sharp LI3033MT Basic,
Style
Unisonic LC-7311BK (5374901) Taiwan
MK65 7 Sharp LI3033MT Basic,
Style
Novus Electronics NS220 Nov. 1981
(6917523)
Taiwan
MK65 A Sharp LI3033MT Basic,
Style
TI-1755
TI-1756
IMA LC 688
(8045735)
(8687189)
(8571527)
Taiwan
MK75   Sharp LI3033MT Basic,
Style
TI-1754
Unisonic LC-7411G
(7863326)
(5917048)
Taiwan
SL6745   unknown Basic,
Style
Technico SL-674CK (------) Taiwan

 

Compal Electronics, Cal-Comp Electronics (Kinpo Electronics)

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

30T 11 CD4565 Scientific TI-30 III C-0185
Jan 1985
Taiwan
CC-11   unknown Basic, Clock Radio Shack EC-260 6A8
Jun. 1978
Taiwan
Cal-Comp
CC-31 A 1 NEC uPD1032G Basic, Clock KMC 2000 (200005 004884)
May 1982
Taiwan
CC-31 B   NEC uPD1032G Basic, Clock Radio Shack EC-303

TI-1788
8A1
Aug. 1981
(9166539)
1981
Taiwan

Taiwan
CC-31-C 10 NEC uPD1032G Basic, Clock TI-1788 II (82862643)
1982
Taiwan
CC-31-T 11 Toshiba T6798S Basic, Clock, Calendar TI-1788 III C-0985
Sep.
1985
Taiwan
(Compal?)
CC-50   NEC uPD1032G Basic, Clock Unisonic LC 7463 ---
Mar. 1982
Taiwan
CL7 13 unknown Basic, Solar
Foldable
TI-1775+ C-0197
Jan 1997
Thailand
JSIA 10 Toshiba T9784 Apothecary New Specialties
Apothecalc
C-1187
Nov. 1987
Taiwan
S4T 10 unknown Basic, Solar TI-1780 C-0983
Sep. 1983
Taiwan
S25T 11 unknown Basic, Solar TI-1606 C-0285
Feb. 1985
Taiwan
S32B-II 1K Sharp LI3135MS Basic, Solar TI-108 C-0888
Aug. 1988
Taiwan
S33T 10 Toshiba Scientific, Solar TI-18 SLR C-0685
Jun. 1985
Taiwan
S39A 11 unknown Basic, Solar
Metric Converter
TI-1895 II C-1186A
Nov. 1986
Taiwan
S39A 12 unknown Basic, Solar
Metric Converter
TI-1895 II

Radio Shack EC-318

TI-1895 II
C-0289A
Feb. 1989
7A0
Jul. 1990
C-0294
Feb. 1994
Taiwan

Taiwan

Thailand
S44T 11 unknown Basic, Solar TI-1626 C-0785
Jul. 1985
Taiwan
SD3 11 unknown Desktop, Solar TI-1797 C-0586
May 1986
Taiwan
SD3 12 unknown Desktop, Solar TI-608 C-0387
Mar. 1987
Taiwan
SD9 10 unknown Desktop, Solar KMC 100B ca. 1984 Taiwan
SD9 11 unknown Desktop, Solar Unisonic XL-1105
(Version 1)
ca. 1984 Taiwan
SD9 13 unknown Desktop, Solar Privileg SOLAR 31

TI-1795

TI-1795
---
ca. 1985
C-0984
Mar. 1984
C-0785A
Jul. 1985
Taiwan

Taiwan

Taiwan
SD9 14 unknown Desktop, Solar Radio Shack EC-2006A

Royal DT 80

TI-1795
 ---
ca. 1986
---
ca. 1986
C-0187A
Jan. 1987
Taiwan

Taiwan

Taiwan
SD9 15 unknown Desktop, Solar TI-1795

TI-1795
C-1087A
Oct. 1987
C-1088A
Aug. 1988
Taiwan

Taiwan
SD9T 10 Sharp LI3135 Desktop, Solar TI-508 C-0690B
Jun. 1990
Taiwan
SD9U 11 unknown Desktop, Solar Unisonic XL-1105
(Version 2)
ca. 1986 Taiwan
SD9L1 10-1 Sharp LI3154 Desktop, Solar TI-1795+

TI-508 PLUS
C-0394D
Mar. 1994
C-0694D
Jun. 1994
Thailand

Thailand
SD10 10 unknown Desktop, Solar Radio Shack EC-2008 ---
ca. 1987
Taiwan
SD29 10-3 Sharp LI3154 Desktop, Solar TI-1795+ (Design Sample) N----
Jun. 1994
Taiwan
SD29 11 Sharp LI3154 Desktop, Solar TI-1795+

TI-1795+

TI-1795+
C-1095
Oct. 1995
C-0498
Apr. 1998
G-0898
Aug. 1998
Thailand

Thailand

China
SD29A 11 unknown Desktop, Solar TI-1796+

TI-1796+
C-0498
Apr. 1998
G-0698
Jun. 1998
Thailand

China

 

Nam Tai Electronics

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

TI-106
DA312
  unknown Basic, Solar TI-1706+ N-1193
Nov. 1993
China
TI-1706NP
JV302
1 unknown Basic, Solar TI-1706+ Prototype ---
Feb. 1996
China
TI-1706NP
JV302
2 unknown Basic, Solar TI-1706+ N-0696
Jun. 1996
China
TI1795NP
JP302, JP307

2, 2
unknown Desktop, Solar TI-1795+ N-0598
May 1998
Taiwan
TI1795SV
VS302, VS307

1, 1
unknown Desktop, Solar TI-1795SV

TI-7350SV

TI-1795SV
N-0300A
Mar. 2000
N-0302B
Mar. 2002
N-0602C
Jun. 2002
China

China

China
TI-1795B MB
1
unknown Desktop, Solar TI-1795SV N-0208F
Feb. 2008
China
TI1800
PD308
3 unknown Desktop, Solar TI-1800 N-0597
May 1997
Taiwan

 

Kinpo Electronics (Desktop Series)

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

138-10 2 unknown Basic, Solar TI-108

TI-108
K-0714
Jul. 2014
L-0216
Feb. 2016
China

Philippines
795E-10 4 unknown Desktop, Solar TI-1795SV K-1007F
Oct. 2007
China
795S-10 2 unknown Desktop, Solar TI-1795SV K-0403D
Apr. 2003
China
795S-12   unknown Desktop, Solar TI-1795SV L-0217K
Feb. 2017
Philippines
796T-10 2 Sharp LI31692R Desktop, Solar TI-1796SV G-0299
Feb. 1999
China
D86T-10 2 unknown Desktop, Solar TI-5018SV G-0401B
Apr. 2001
China

 

Kinpo Electronics (Scientific Series)

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

SR10T-10 3 unknown Scientific, Solar TI-10 K-0407
Apr. 2007
Taiwan
SR15T-10 3 unknown Scientific, Solar TI-15 Explorer K-1007A
Oct. 2007
Taiwan

 

Toshiba Corporation

PCB Mark

Rev.

Calculator Chip

Function

Calculator

Date Code
(Serial #)

Country of Manufacture

TI-1776II   Toshiba T6789S Basic, Solar TI-1776 122
Dec. 1982
Japan
TI-1895 21 Toshiba T6856S Basic, Solar
Metric Converter
TI-1895 T-0684
Jun. 1984
Japan

 

horizontal rule

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

Joerg Woerner, March 12, 2020. No reprints without written permission.