DATAMATH CALCULATOR MUSEUM |
Royal DT 80 (Version 1)
Date of introduction: | 1984 | Display technology: | LCD |
New price: | Display size: | 8 | |
Size: | 4.7" x 4.1" x
1.0" 120 x 106 x 25 mm3 |
||
Weight: | 3.0 ounces, 86 grams | Serial No: | |
Batteries: | n.a. | Date of manufacture: | mth 10 year 1984 |
AC-Adapter: | Origin of manufacture: | Taiwan | |
Precision: | 8 | Integrated circuits: | Sharp LI3135MS |
Memories: | 1 | ||
Program steps: | Courtesy of: | Joerg Woerner |
Does
this Royal DT 80 calculator sold in 1984 look familiar to you?
Dismantling
the featured DT 80 manufactured in October 1984 by
Cal-Comp Electronics, an
OEM (Original Equipment Manufacturer) in Taiwan, reveals a clean design
centered around a Sharp LI3135MS single-chip calculator circuit soldered on a
double-sided printed circuit board (PCB) and powered by solar cells.
Inspecting the PCB of this
DT 80 brought our attention to a small mark reading
SD9-12, most likely a reference to Type
Small Desktop 9 and Revision
1.2
of the design (schematics and layout). We spotted similar PCB-Mark already with the near identical offspring
TI-1795 and Radio Shack
EC-2006A with revisions
SD9-13, SD9-14, and SD-9-15. We started compiling a list
of the PCB-Marks on calculators
manufactured by OEMs for Texas Instruments.
The DT 80 was soon replaced replaced with a 2nd
Version sporting smaller solar cells.
If you have additions to the above article please email: joerg@datamath.org.
© Joerg Woerner, August 2, 2023. No reprints without written permission.