DATAMATH CALCULATOR MUSEUM
Texas Instruments TI-1795+ (1996 Cal-Comp)
|Date of introduction:||January 1996||Display technology:||LCD|
|New price:||Display size:||8|
|Size:|| 5.1" x 4.2" x 1.0"
130 x 106 x 26 mm3
|Weight:||3.3 ounces, 94 grams||Serial No:|
|Batteries:||n.a.||Date of manufacture:||mth 10 year 1995|
|AC-Adapter:||Origin of manufacture:||Thailand (C)|
|Precision:||8||Integrated circuits:||Sharp LI3154|
|Program steps:||Courtesy of:||Joerg Woerner|
first glance looks this TI-1795+ almost identical to the first design of the TI-1795+,
main differences are the slightly rounder design of the housing and a new layout
of the keys in the left column.
Dismantling this TI-1795+ manufactured already in October 1995 by Cal-Comp Electronics in Thailand and a second unit from April 1998 reveals a clean design centered around a Sharp LI3154 single-chip calculator circuit soldered on a double-sided printed circuit board (PCB). We noticed this chip during our research about so-called Checkbook Calculators with the Radio Shack EC-455. Learn more about single-chip calculator circuits used in Account Manager Calculators.
LI3154 is packaged in a standard Flat Pack (FP) housing, a very uncommon approach mid
of the 90s. Most calculators of this era use "Chip-on-Board"
(COB) technology, instead. Please compare it
with a TI-1795+ and TI-7350 manufactured in China,
too. Inventec Corporation on
the other hand manufactured even in 2007 the BA-20
Profit Manager with a conventional Quad Flat Pack (QFP) housing.
Inspecting the PCBs of the two TI-1795+ calculator brought our attention to a small mark reading SD29-11, most likely a reference to Type Small Desktop 2nd Design 9 and Revision 1.1 of the design (schematics and layout). We spotted a very similar PCB-Mark already with the Radio Shack EC-2006A and Privileg SOLAR 31. We started compiling a list of the PCB-Marks on calculators manufactured by OEMs for Texas Instruments.
The Second Generation of the TI-1795+ was introduced in January 1996 and an interesting journey around the Globe began:
TI-1795+ Second Generation Prototype
Kinpo Electronics (Taiwan),
• TI-1795+ Second Generation Cal-Comp Electronics (Thailand), October 1995 and April 1998
• TI-1795+ Second Generation Nam Tai Electronics (China), May 1998
• TI-1795+ Second Generation Kinpo Electronics (China), August 1998
A similar calculator with 10 digits of display capability was sold with the TI-1796+.
Press the X-RAY
button and view the internals of a TI-1795+.
Look carefully and you'll notice the odd battery compartment!
(Pictures provided by Edward Soudentas)
If you have additions to the above article please email: firstname.lastname@example.org.
© Joerg Woerner, April 9, 2020. No reprints without written permission.