Unisonic LC 263CK

Date of introduction:  June 1981 Display technology:  LCD
New price:  $27.95 (SRP June 1982) Display size:  8
Size:  2.8" x 6.0" x 0.30"
 72 x 153 x 8 mm3
Weight:  2.6 ounces, 74 grams Serial No:  20521447
Batteries:  2*LR44 Date of manufacture:  year 1982
AC-Adapter:   Origin of manufacture:  Japan
Precision:  8  Integrated circuits:  NEC uPD1833G
Memories:  3    
Program steps:   Courtesy of:  Joerg Woerner
    Download manual:   (US: 1.1 MByte)

Unisonic entered the market of Checkbook Calculators with the LC 262 in 1979. It features Account Manager functionality with three permanent (till you remove the batteries) Memories and started a very successful product line. We discovered as of now ten different family members:

1979: LC 262, 3 Memories, Credit Card size
1981: LC 262CK, 3 Memories, Credit Card size
1981: This LC 263CK, 3 Memories
1981: LC 224CK, 1 Memory
1982: LC 224CKE, 1 Memory, Pen
1983: LC 224CKM, 1 Memory, Pen
1983: LC 223CK, 1 Memory, Credit Card size
1985: LC 225CK, 1 Memory
1987: LC 266CK, 3 Memories, Taiwan
1988: LC 226CK, 1 Memory, Taiwan
1990: LC 226CK, 1 Memory, Thailand

Dismantling the featured LC 263CK manufactured in 1982 in Japan 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.

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