DATAMATH  CALCULATOR  MUSEUM

IMA 130CBW

Date of introduction:  June 1982 Display technology:  LCD
New price:   Display size:  8
Size:  2.8" x 6.0" x 0.30"
 71 x 154 x 8 mm3
   
Weight:  2.8 ounces, 80 grams Serial No:  
Batteries:  2*LR44 Date of manufacture:  year 1982
AC-Adapter:   Origin of manufacture:  Hong Kong
Precision:  8  Integrated circuits:  NEC uPD1833G
Memories:  3    
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (US: 1.6 MByte)

National Semiconductor introduced already in 1978 with the NS103 Data Checker an electronic record keeper with three continuous memories to track bank and charge account balances with dedicated keys:

Memory 1 [CHK] [DEP] [BAL] [A]
Memory 2 [PMT] [CHG] [BAL] [B]
Memory 3 [PMT] [CHG] [BAL] [C]
Total sum of Memories [GT]

While the NS103 Data Checker was based on proprietary technology, introduced NEC of Japan with the uPD1833G in 1980 a single-chip calculator circuit that created the blueprint for checkbook-sized Account Manager calculators and thereupon the market got swamped with products based on this design. The uPD1833G simplified the use of the memories by removing the redundant [A], [B], and [C] keys and replaced the inconvenient three-way power-switch of the NS103 Data Checker with two dedicated [ON] and [OFF] keys and a [DS] key to toggle between two entry modes:

Indicator (--) Floating decimal with manual insertion of the decimal using the [.] key
Indicator (AM) Add mode with the decimal automatically put in the dollars and cents position (0.00)

Even the successor of the NS103, known as NS103A, switched its internals to the uPD1833G but we feature some more Account Manager calculators in the Datamath Calculator Museum based on this technology:

Canon Checkbook - Missing the Toggle Key for the decimal mode
Royal LCB 841 - The Art of Perfection in Japan
Royal LCB 835 - Just one Memory (uPD1831G)
Texas Instruments TI-2200 Checkwriter - Late, but not too late
This Unisonic LC 262CK Check Master - Credit Card sized

NEC of Japan lost some market share with their design for Account Manager calculators in the Eighties, when competitors like Hitachi and Sharp introduced similar chips and finally lost the business completely to Toshiba's "Solar Cells" compatible design. Find more Account Manager calculators in the Datamath Calculator Museum:

Canon Checkbook II - Toshiba inside
Casio CB-80 - Hitachi inside
Unisonic LC 224CK Check Master - Sharp Inside
Texas Instruments TI-2200 II Checkwriter - Toshiba + Solar cells = Winning formula

Dismantling the featured IMA 130CBW manufactured in 1982 in Hong Kong by IMA-Hong Kong, the Asian subsidiary of Spectra Merchandising International, Inc of Chicago, IL, reveals a clean design centered around a NEC uPD1833G single-chip calculator circuit powered by two small LR44 batteries.

Learn more about single-chip calculator circuits used in Account Manager Calculators.

Does this IMA 130CBW Electronic Checkbook Calculator look familiar to you? Please compare it with the Radio Shack EC-306 introduced in 1984 and manufactured in Hong Kong, too. The two printed circuit boards look almost identical but the EC-306 sports a PCB Mark 2310306-01 while the 130CBW reads 39P852 IP6501.

Don't miss the Corvus CheckMaster introduced by Mostek already in 1975. This rare product retains the balance of your memory even when shut off but uses power-hungry electronics.



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

Joerg Woerner, February 6, 2020. No reprints without written permission.