citation 66 4986 7Model: Citation (66-4986-7)
Battery: 9 volt
Adapter: 
Year: 1978
Chip: TMC0921
Info: If you remove the key-plate known from e.g. the "electronic Wizard" from this Citation you'll get a TI-1050. Everything else is identical, even the back of the calculators tells you the manufacturer Texas Instruments.