Texas Instruments

• Overhead

Model: TI-15 overhead
Battery: 
Adapter: 
Year:  
Chip: made in China
Info:  The California based company Stokes Publishing Company, Inc. distributes under the label "The Educator®"
calculators optimized for teaching purposes. William T. Stokes filed already July 30, 1991 the US Patent Application U.S. Pat. No. 5,035,502
 with the title "Transparent calculator for overhead projection".

• Basic
• Rare

Model: TI-150
Battery: 4 x AA ni-cd internal
Adapter: AC9150
Year: 1975
Chip: TMS0852
Info: This calculator tastes different, it was a dear friend Joerg of datamath.org who gave it to me.

Very Rare

• Basic

Model: TI-1500
Battery: 2 x AA ni-cd
Adapter: AC9140, AC9900/C
Year: 1974
Chip: TMS0803
Info: 

• LCD-1985-1990

Model: TI-1505
Battery: LR1130
Adapter: 
Year: 1985
Chip: 
Info: LCD  1985 - 1990  Made in Taiwan

• Basic

Model: TI-1600
Battery: special 1,2 ni-cd
Adapter: AC9131
Year: 1977
Chip: TMS1043
Info: