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Royal LCB 835

Date of introduction:  1983 Display technology:  LCD
New price:  $22.95 (SRP September 1983) Display size:  8
Size:  2.6" x 6.0" x 0.25"
 65 x 153 x 6 mm3
   
Weight:  2.9 ounces, 81 grams Serial No:  
Batteries:  LR54 Date of manufacture:  mth 07 year 1983
AC-Adapter:   Origin of manufacture:  Taiwan
Precision:  8  Integrated circuits:  NEC uPD1831G
Memories:  3    
Program steps:   Courtesy of:  Ken H. Meine
    Download manual:   (US: 1.7 MByte)

Royal Typewriters and its sister company Triumph-Adler, part of Litton Industries, were sold in 1986 to Olivetti and is since September 2004 a private American company again and is today known as Royal Consumer Information Products Inc.

Royal entered the market of Checkbook Calculators with the LCB 841 in August 1980. 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 eleven different family members:

1980: This LCB 841, 3 Memories
1983: Royal LCB 830, 1 Memory, Wallet
1983: This Royal LCB 835, 1 Memory, Purse
1986: Royal CBC 80NT, Solar cells, Taiwan, 3 Memories
1987: Royal CBC 70, Taiwan, 1 Memory
1988: Royal CBC 80, Solar cells, Thailand, 3 Memories, US market
1988: Royal/Olivetti CBC 80, Solar cells, Thailand, 3 Memories, Canadian market
1988: Olivetti DII Solar cells, Thailand, 3 Memories, European market
1989: Royal CBC 70, Thailand, 1 Memory
1993: Royal CBC 95, Solar cells, Thailand, 3 Memories
1998: Royal CBC 2000, Solar cells, China, 3 Memories

Dismantling the featured LCB 835 Checkbook Calculator manufactured in July 1983 in Taiwan reveals a clean design centered around a NEC uPD1831G single-chip calculator circuit soldered on a one-sided printed circuit board (PCB) and powered by two small LR54 (LR1130) batteries. NEC introduced with the uPD1831G a variation of the original uPD1833G design sporting just on memory. We located this calculator chip in "regular" calculators, too. Don't miss the TI-1744 and learn about the full feature set of the uPD1831G with the Canon card F-32 Mathematic Calculator.


Inspecting the PCB of the LCB 835 calculator brought our attention to a small jumper to select between:

(MR) Checkbook Calculator: [BAL/MR] doesn't clear the Memory
(MRC) Standard Calculator: [MRC] does clear the Memory

In addition did we notice on the PCB of this LCB 835 manufactured in July 1983 a small mark reading 830A-10, most likely a reference to Type 830, Alternate design and Revision 1.0 of the design (schematics and layout).

Please find an overview of the PCB-Marks we discovered so far on Account Manager calculators.

Comparing this LCB 835 sporting a 830A-10 mark and a LCB 830 with a 830-10 mark manufactured a few month earlier, reveals some interesting differences:

PCB Mark

Rev.

Calculator Chip

Date Code

PCB Jumper

PCB Technology

830 10 NEC uPD1832G 8316 (MR), (MRC), (N) single-sided, wire jumpers in 3 different length
830A 10 NEC uPD1831G 8327 (MR), (MRC), 4*(A) single-sided, conductive print over PCB traces

The NSC Novus Electronics NS 101A (First Design) and NS 101A (Second Design) went through the same changes in PCB technology.

This Royal LCB 835 and its twin LCB 830 are obviously based on an OEM design shared with other manufacturers. Compare the Aurora CB-900.

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. Interested in Purse Calculators? Don't miss the Arizona CB82 Check Tronic.



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

Joerg Woerner, February 5, 2020. No reprints without written permission.